Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Variant 3: Nontraumatic chest wall pain. Suspected infectious or inflammatory condition. Secondary evaluation after normal chest radiograph. Next imaging study. Bone Scan Whole Body Nuclear medicine studies, including bone scans and radiolabeled WBC scans, are especially helpful in localization of infectious or inflammatory conditions of the bones, joints, and costal cartilages, especially in the setting of negative radiographs and CT and in patients with metallic implants [47,48]. Bone scintigraphy is useful in screening the entire body for occult infectious or inflammatory disease, especially for patients with fever of unknown origin [26].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Nontraumatic Chest Wall Pain


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. CT Chest CT is superior to US and radiography in determination of disease extent, including characterization of deep compartments and intrathoracic involvement. Osseous involvement, including cortical erosion, fragmentation, and sequestra, are readily depicted on CT. Gas formation within necrotic tissues or in the setting of serious infections, such as necrotizing fasciitis, is easily depicted on CT [48,52]. Chronic chest wall infections (eg, empyema necessitans, actinomycosis, Aspergillus) are well characterized with CT [52]. Administration of IV contrast may help to characterize and define fluid collections and soft-tissue sinus tract formation. Advantages of CT include rapid image acquisition, isotropic data, and high spatial resolution. Limitations include decreased sensitivity related to streak artifacts around metallic hardware. CT may be utilized for image-guided drainage procedures or during percutaneous biopsy.


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. MRI Chest MRI is highly effective at detecting and characterizing infectious and inflammatory disorders of the chest wall soft tissues and osseous structures, maintaining a high negative predictive value in excluding disease in the setting of normal imaging findings [48,58]. Fluid-sensitive sequences, especially those with applied fat signal suppression, detect early edema and readily define extent of soft tissue and osseous involvement that may not be apparent on CT [52]. Administration of gadolinium-based contrast material further characterizes areas of hyperemia and defines fluid collections and soft-tissue sinus tract formation. Unlike CT, gas formation is not as well appreciated on MRI but may be seen as signal void, especially on gradient-echo sequences [48]. MRI may be useful for defining infectious involvement of skin and fascial layers, muscle, bursae, and tendons. If clinical suspicion for potentially life-threatening necrotizing fasciitis is high, detection of hyperintense signal within chest wall deep fascial compartments on fluid-sensitive MRI sequences is highly suggestive of the disease, and the absence of these findings essentially exclude the disease [48,58]. MRI also serves a role in surgical planning prior to debridement procedures, distinguishing viable from nonviable tissue based on tissue signal and enhancement characteristics [48]. MRI may be helpful in the differentiation of chest wall infection from tumor.


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Anterior chest wall pain is a common complaint among patients who have underlying spondyloarthritis, but the diagnosis may be delayed for many years [53]. MRI was 62.5% sensitive in determining sternoclavicular and sternocostal involvement by inflammatory spondyloarthritis in patients who presented with anterior chest wall pain as an early manifestation of their disease and was able to provide specific information regarding disease activity and severity beyond that provided by bone scintigraphy [49]. Another study showed higher sensitivity of MRI for detection of disease activity (bone marrow edema, erosions, and fat infiltration) than other serologic and clinical


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Nontraumatic Chest Wall Pain parameters, and especially involvement of the manubriosternal joint [59]. Other systemic inflammatory conditions can also be suggested by MRI with abnormal signal intensity of skeletal muscle (whether from edema or fatty atrophy), such as immune-mediated myositis and other neurodegenerative diseases [48].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Radiography Rib Views There is no relevant literature to support the use of radiography rib views beyond chest radiography in the primary evaluation of chest wall pain in patients with suspected chest wall infectious or inflammatory conditions.


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. US Chest US is a useful modality for targeted evaluation of soft tissue, osseous, and joints of the chest wall and for characterization and potential drainage of abscesses and joint effusions but has limited capability of determining extent of disease [48].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Variant 4: Nontraumatic chest wall pain. History of prior chest intervention. Secondary evaluation after normal chest radiograph. Next imaging study. Bone Scan Whole Body A single case report described bone scan findings of heterogeneous radiotracer uptake in ribs that were within the areas of the chest wall that received >30 Gy after a chest CT revealed no abnormality [62]. In a case report of a patient with chest pain 11 months after chest wall radiation for breast cancer, a bone scan showed evidence of costochondritis but no metastases after initial negative CT and were both later positive after the patient developed rib fractures [63].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Bone scan or radiolabeled WBC scan plays a role in the evaluation of sternal osteomyelitis, especially in patients who have equivocal CT findings, maintaining a high negative predictive value for osteomyelitis [64].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. CT has variable performance in the diagnosis of sternal wound infections after cardiac surgery. Most patients may present with clinical signs and symptoms of sternal infection, precluding the need for imaging. However, CT may be useful for diagnosis in patients in whom the diagnosis is suspected but who lack overt clinical signs and symptoms [64,67]. In a study of 40 patients, the sensitivity and specificity of CT for diagnosis of mediastinitis was best beyond 17 days after surgery (100% and 90%, respectively), with 100% sensitivity and only 33% specificity in the first 17 postoperative days [68,69].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Noninfectious poststernotomy chest pain may affect more than half of patients after sternotomy and was inversely correlated with the degree of osseous healing (complete versus incomplete) [8]. Sternal nonunion and sternal dehiscence may be characterized at CT, with sternal gap >3 mm correlating with significantly higher chest pain intensity compared with those with minor dehiscence and those with normal sternal healing, as determined by chest CT [8,64,70]. Chest CT with 3-D reconstructions was useful in assessing the degree of healing and residual chest wall deformities in 46 patients randomized to either operative or nonoperative management of flail chest [71]. CT is commonly used in the pre- and postoperative evaluation of patients who underwent chest wall reconstruction for rib fractures and chest wall tumors [72,73]. Rarely, desmoid-type fibromatosis can occur at prior thoracotomy sites


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Nontraumatic Chest Wall Pain and may mimic chest wall recurrence. CT in combination with FDG-PET/CT is useful for detecting and characterizing these lesions and for image-guided biopsy [74].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. FDG-PET/CT Skull Base to Mid-Thigh Investigators have shown a positive dose-dependent relationship in chest wall FDG-PET/CT uptake predictive of patients who later developed chest wall complications (pain and rib fractures) after stereotactic body radiation therapy for lung cancer [75]. False-positive diagnoses can occur in cases in which there is myositis-related FDG uptake in the chest wall musculature in patients who have undergone prior radiation [76]. Furthermore, FDG- PET/CT is valuable in determining depth of infection, involvement of costal cartilages, and for preoperative planning of debridement procedures in patients with deep sternal wound infections after sternotomy procedures [77]. The sensitivity and specificity of FDG-PET/CT for sternal wound infections was 91% and 97%, respectively, with SUVmax showing value in patients who are imaged >6 months after surgery [78].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. MRI Chest Chest MRI is valuable in the evaluation of patients after treatment of chest wall neoplasms and is superior to chest CT for detection of sites of residual or recurrent tumor after chest radiation or resection, especially using T1- weighted fat-suppressed sequences after administration of gadolinium-based contrast material [27]. MRI may also be used to determine the etiology of rib fractures in patients with known malignancy [63]. MRI has been also used in follow-up and response evaluation of patients with chest wall and breast desmoid tumors that developed after mastectomy and silicone implant augmentation [79].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Chest MRI may be a valuable tool in the early detection of sternal wound infections, given its high spatial resolution and soft-tissue contrast, but is limited by susceptibility artifacts related to sternotomy wires and other cardiac implants [69].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Radiography Rib Views There is no relevant literature to support the use of radiography rib views beyond chest radiography in the primary evaluation of chest wall pain in patients with prior chest wall intervention.


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. US Chest Apart from targeted evaluation of the chest wall soft tissues for hematoma or abscess evaluation or treatment after chest wall surgery, US has a limited role. One study utilized sternal US to assess for sternal nonunion with dynamic compression and cortical sliding as a cause for poststernotomy chest pain [70].


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. WBC Scan Chest There is sparse literature to support the use of WBC scans in the primary evaluation of patients who present with chest wall pain after previous intervention. Quirce et al [80,81] compared the diagnostic performance of planar and SPECT WBC scans among 41 patients with suspected sternal infections after sternotomy, showing superior performance of SPECT over planar imaging for detection of infections at both 4 and 20 hours after injection and for differentiating superficial from deeper infections.


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Supporting Documents The evidence table, literature search, and appendix for this topic are available at https://acsearch.acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation.


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. For additional information on the Appropriateness Criteria methodology and other supporting documents go to www.acr.org/ac.


Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain

Nontraumatic Chest Wall Pain. Nontraumatic Chest Wall Pain


Postpartum Hemorrhage

Postpartum Hemorrhage. Introduction/Background Postpartum hemorrhage (PPH) is among the top three causes of maternal death in the United States and accounts for 27% of all maternal deaths worldwide [1,2]. PPH affects 1% to 5% of all deliveries and may be life-threatening. PPH in the first 24 hours after delivery is termed primary or early PPH, whereas after 24 hours to 6 weeks it is termed secondary, late, or delayed PPH. Although classically, PPH has referred to pregnancies delivered beyond 20 weeks of gestation, the definition may be expanded to include hemorrhage post terminations or early pregnancy loss [3]. PPH is defined as any hemorrhage associated with signs or symptoms of hypovolemia within 24 hours of delivery, regardless of the type of delivery [4].


Postpartum Hemorrhage

Postpartum Hemorrhage. Conservative measures such as uterine tamponade with either packing or balloon catheter and massage, uterotonic medications, and correction of coagulopathies are the first line of treatment. Once a specific diagnosis has been identified, tailored intervention such as curettage for RPOC, embolization for VUA, antibiotics for infection, evacuation of large bladder hematoma, or surgical repair for uterine rupture can be performed. Uterine artery embolization, surgical ligation of uterine/internal iliac arteries, or hysterectomy may be necessary if these measures fail. Of special note is the evolving diagnosis and management of VUA. Myometrial VUA are believed to represent subinvolution of the placental bed, may be associated with RPOC, and will resolve either with removal of RPOC or expectant management in most patients. Timmerman et al [7] has reported an increased risk of significant PPH in those areas of intense myometrial vascularity with peak systolic velocity >83 cm/s. A subsequent report by the same group indicated surgical removal of RPOC would also result in almost immediate resolution of these areas of intense myometrial vascularity [8,9]. Multidisciplinary consultation may aid in optimal management protocols in this group of patients with VUAs, RPOC, and PPH.


Postpartum Hemorrhage

Postpartum Hemorrhage. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through society representation on expert panels. Participation by representatives from collaborating societies on the expert panel does not necessarily imply individual or society endorsement of the final document.


Postpartum Hemorrhage

Postpartum Hemorrhage. Reprint requests to: publications@acr.org


Postpartum Hemorrhage

Postpartum Hemorrhage. All elements are essential: 1) timing, 2) reconstructions/reformats, and 3) 3-D renderings. Standard CTs with contrast also include timing issues and recons/reformats. Only in CTA, however, is 3-D rendering a required element. This corresponds to the definitions that the CMS has applied to the Current Procedural Terminology codes.


Postpartum Hemorrhage

Postpartum Hemorrhage. Pelvic angiography has not been included in this document because the clinical utility of pelvic angiography has a very limited role as an isolated diagnostic imaging study. Pelvic angiography in the setting of PPH is primarily used to perform therapeutic interventions, which is not within the scope of this document.


Postpartum Hemorrhage

Postpartum Hemorrhage. OR Discussion of Procedures by Variant Variant 1: Postpartum hemorrhage. Early (within first 24 hours) after cesarean delivery. Initial imaging. The most common cause of early PPH is related to uterine atony or lack of effective uterine contraction after delivery and is typically a clinical diagnosis in >75% of patients. It is initially treated by uterine massage and uterotonic drugs such as oxytocin, and the majority of patients respond well to these treatments. In the setting of cesarean section, because the abdomen is already open, surgical procedures to control intraoperative and immediate hemorrhage such as uterine or ovarian artery ligation or uterine compression sutures may be utilized. If there is no response, additional considerations would include associated RPOC, adherent placentation, or even uterine inversion, and in these situations, imaging may be helpful. About 1% of third trimester deliveries are complicated by RPOC [11] and is the second most common etiology for PPH after uterine atony; although, this is typically seen in the delayed PPH population. The diagnosis of RPOC is helpful to the clinician in determining whether surgical intervention is warranted. Trauma-related hemorrhage may be due to lacerations, uterine rupture, or incision extensions. Imaging may be helpful to delineate the extent of intra-abdominal hemorrhage, whereas infralevator or perineal hemorrhage may be evaluated on visual inspection. Coagulopathy, either inherited or acute related to amniotic fluid embolism, placental abruption, severe pre-eclampsia or hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome, is less common but potentially life threatening. There is a long list of risk factors associated with uterine atony, which is not within the scope of this document.


Postpartum Hemorrhage

Postpartum Hemorrhage. CT Abdomen and Pelvis In the setting of hemorrhage, the primary role of CT is to determine whether active ongoing hemorrhage is present, to localize the bleeding, and to identify the source, which is best accomplished with a CT with intravenous (IV) contrast. There is little clinical utility in a noncontrast CT or CT with and without IV contrast in the setting of active ongoing hemorrhage. In hemodynamically stable patients when conventional medical treatment has been unsuccessful in terminating hemorrhage, further evaluation with CT can be considered, particularly in suspected intra-abdominal hemorrhage or postsurgical complications [12]. CT has a role in identifying surgical causes of PPH, which will not benefit from empiric embolization such as uterine rupture and genital tract laceration.


Postpartum Hemorrhage

Postpartum Hemorrhage. Although uterine atony is a clinical diagnosis, CT can be helpful by detecting a hematoma within the cavity of an enlarged uterus [13] and excluding other causes of PPH. However, it can be difficult to differentiate blood products from RPOC [12].


Postpartum Hemorrhage

Postpartum Hemorrhage. CT can detect vascular complications such as bladder flap, subfascial, or perivaginal space hematoma and delineate relationship to adjacent organs (supralevator versus infralevator location in the perivaginal space) [14,15]. Small (<4 cm) subfascial and bladder flap hematomas may not be clinically significant [15]. A >5 cm bladder flap


Postpartum Hemorrhage

Postpartum Hemorrhage

Postpartum Hemorrhage. Postpartum Hemorrhage


Postpartum Hemorrhage

Postpartum Hemorrhage. hematoma should raise suspicion for uterine dehiscence, characterized by disruption of the endometrial and myometrial layers with an intact serosal layer [15,16]. Low correlation between clinical and radiologic findings of dehiscence have been noted, and it is important not to interpret hypodense edema at the cesarean incision site as dehiscence in the first postpartum week [15]. Presence of gas in the myometrial defect extending from the endometrium to the parametrial tissue along with hemoperitoneum are findings suggestive of uterine rupture [15].


Postpartum Hemorrhage

Postpartum Hemorrhage. CTA Abdomen and Pelvis Persistent hemorrhage after empiric embolization is an indication for CTA [12]. Active extravasation is seen in 41% to 74% cases of PPH on CTA [17] and multiphasic CT, including a noncontrast arterial and portal venous phases, has excellent accuracy of 97% [18] for detection of the site of active extravasation, similar to that of gastrointestinal hemorrhage [17,18]. CTA can be falsely positive because of dilated tortuous hypertrophic uterine arteries mimicking extravasation and be falsely negative in atony because of slow intermittent hemorrhage [12,18]. CTA also enables comprehensive evaluation of abdominopelvic vasculature, including vessels not often evaluated on routine angiography such as the ovarian and inferior epigastric arteries [18].


Postpartum Hemorrhage

Postpartum Hemorrhage. Serpiginous myometrial vessels and prominent parametrial vessels can be a sign of VUA [19], whereas the presence of a pseudoaneurysmal sac is a more specific finding [14,20,21]. CTA can also identify and localize the feeding arteries of arteriovenous malformation (AVM) for treatment planning [14]. However, CTA cannot reliably distinguish acquired VUA from failure of obliteration/subinvolution of the placental bed vessels, assess its severity, or need for intervention [19].


Postpartum Hemorrhage

Postpartum Hemorrhage. MRI Pelvis MRI is not commonly used in significant life-threatening early PPH as CT, in part related to access and time required to perform the study in an acute setting. MRI has an important role to play in distinguishing and/or confirming uterine dehiscence versus rupture, in particular when it is confusing on ultrasound (US) or CT.


Postpartum Hemorrhage

Postpartum Hemorrhage. Although RPOC can be seen as an intracavitary mass with variable signal characteristics, distinction from blood products is limited in the absence of contrast administration. MRI is better than CT and US in detecting the myometrial defect with intact serosal layer in uterine dehiscence because of superior soft-tissue contrast [14,15]. However, in the immediate postpartum period, the cesarean section incision can be T1 and T2 hyperintense and may mimic a dehiscence [22].


Postpartum Hemorrhage

Postpartum Hemorrhage. Noncontrast MRI can be used to identify bladder flap, subfascial, and deep-seated pelvic hematomas, which depending on the time since delivery may demonstrate variable T1 and T2 signal characteristics [14,23]. The superior spatial resolution of MRI compared to US enables localization of the hematoma (eg, supralevator versus infralevator location in the perivaginal space) for potential targeted intervention [23].


Postpartum Hemorrhage

Postpartum Hemorrhage. On MRI fast-spin echo sequences, AVM demonstrates serpiginous signal voids with prominent parametrial vessels and focal disruption of the junctional zone [14]. VUA can also be seen on MRI fast-spin echo sequence as serpiginous signal voids with prominent parametrial vessels, whereas the presence of a pseudoaneurysm sac is more specific [14,20]. Failure of obliteration of the placental bed vessels after pregnancy cannot be reliably distinguished from acquired VUA on MRI [19].


Postpartum Hemorrhage

Postpartum Hemorrhage. US Duplex Doppler Pelvis Transabdominal US is often performed in conjunction with transvaginal US and color or power Doppler and should be considered a single examination. Color and spectral Doppler are commonly employed in pelvic sonography to detect the presence of vascular flow in normal anatomic structures as well as various pathologic lesions. In women with PPH, Doppler improves the specificity and negative predictive value of detecting RPOC by detecting vascularity within a thickened endometrial echo complex [24]. When a pseudoaneurysm is suspected, color and spectral Doppler can detect swirling or yin-yang pattern of blood flow within a hypoanechoic structure [14,20].


Postpartum Hemorrhage

Postpartum Hemorrhage. Pitfalls in assessment include that absence of vascularity could represent an avascular RPOC [12] and marked vascularity can mimic a pseudoaneurysm, although RPOC generally extends to the endometrium, whereas pseudoaneurysm is restricted to the myometrium [25]. However, it can be difficult to distinguish acquired VUA from subinvolution of the placental bed [19,26] or to assess its severity or need for intervention on US [19]. Although high peak systolic velocities have been used to predict need for intervention, there is considerable overlap [7].


Postpartum Hemorrhage

Postpartum Hemorrhage


Postpartum Hemorrhage

Postpartum Hemorrhage. US Pelvis Transvaginal A combined transabdominal and transvaginal approach is the primary modality of choice for the investigation of early PPH not responsive to initial conservative measures. Although transvaginal US detection of an echogenic endometrial mass has the highest sensitivity for the detection of RPOC, this is a nonspecific finding that overlaps with the normal postpartum appearance [14]. The most diagnostic combination of US findings is an echogenic endometrial mass that is vascular [27]. The presence of debris and gas is relatively common in the early postpartum period, in as much as 20% to 25%. Thickened endometrial echo complex, up to 2 to 2.5 cm in diameter, is nonspecific in this early postpartum period [28].


Postpartum Hemorrhage

Postpartum Hemorrhage. US can be used in this setting to assess for coexisting pathology and complications, such as RPOC or hematoma. US can detect most pelvic hematomas [13], including bladder flap hematomas [14,15]. Although uterine scar dehiscence may be seen on US as an irregular thinned uterine wall or a myometrial defect [14], differentiation from the normal appearance of the cesarean section scar can be difficult.


Postpartum Hemorrhage

Postpartum Hemorrhage. VUA, including uterine artery pseudoaneurysm, are a relatively rare cause of early PPH, occurring particularly in the traumatic setting [19,20], and most commonly arise from the uterine artery. VUA appear as hypoechoic tortuous channels or masses in the myometrium with characteristic Doppler findings [14,19] with turbulent flow on color Doppler and high-velocity and low-resistance flow on spectral analysis and may be associated with a peripheral echogenic hematoma [20].


Postpartum Hemorrhage

Postpartum Hemorrhage. It can be difficult to distinguish acquired VUA from subinvolution of the placental bed [19,26] or to assess its severity or need for intervention on US [19]. A dilated vessel in the myometrium may suggest the diagnosis of pseudoaneurysm.


Postpartum Hemorrhage

Postpartum Hemorrhage. Variant 2: Postpartum hemorrhage. Early (within first 24 hours) after vaginal delivery. Initial imaging. The most common cause of early PPH is related to uterine atony or lack of effective uterine contraction after delivery and is typically a clinical diagnosis in >75% of patients. It is initially treated by uterine massage and uterotonic drugs such as oxytocin, and the majority of patients respond well to these treatments. If there is no response, additional considerations would include associated RPOC, adherent placentation, or even uterine inversion, and in these situations, imaging may be helpful. About 1% of third trimester deliveries are complicated by RPOC [11] and is the second most common etiology for PPH after uterine atony; although, this is typically seen in the delayed PPH population. The diagnosis of RPOC is helpful to the clinician in determining whether surgical intervention is warranted. Trauma-related hemorrhage may be due to lacerations, uterine rupture, or incision extensions. Imaging may be helpful to delineate the extent of intra-abdominal hemorrhage, whereas infralevator or perineal hemorrhage may be evaluated on visual inspection. Coagulopathy, either inherited or acute related to amniotic fluid embolism, placental abruption, severe pre-eclampsia or HELLP syndrome, is less common but potentially life threatening. There is a long list of risk factors associated with uterine atony, which is not within the scope of this document.


Postpartum Hemorrhage

Postpartum Hemorrhage. CT Abdomen and Pelvis In the setting of hemorrhage, the primary role of CT is to determine whether active ongoing hemorrhage is present, to localize the bleeding, and to identify the source, which is best accomplished with a CT with IV contrast. There is little clinical utility in a noncontrast CT or CT with and without IV contrast in the setting of active ongoing hemorrhage. In hemodynamically stable patients, when conventional medical treatment has been unsuccessful in terminating hemorrhage, multiphasic CT can be useful in localizing the source of extravasation for targeted therapy [12,29], particularly in suspected intra-abdominal hemorrhage [12].


Postpartum Hemorrhage

Postpartum Hemorrhage. Although uterine atony is a clinical diagnosis, CT can be helpful by detecting focal or diffuse arterial or venous oozing and/or hematoma within the cavity of an enlarged uterus [13]. RPOC can be difficult to differentiate from blood products even on multiphase CT [12]. Endometritis is a clinical diagnosis with a nonspecific CT appearance of a thickened heterogeneous endometrium with fluid, gas, and debris within the cavity [15].


Postpartum Hemorrhage

Postpartum Hemorrhage

Postpartum Hemorrhage. Postpartum Hemorrhage


Postpartum Hemorrhage

Postpartum Hemorrhage. CT can detect vascular complications such as supraumbilical and perivaginal space hematoma and delineate the relationship to adjacent organs (supralevator versus infralevator location in the perivaginal space) for targeted intervention [12,14,15,30].


Postpartum Hemorrhage

Postpartum Hemorrhage. CTA Abdomen and Pelvis Persistent hemorrhage after empiric embolization is an indication for CTA [12]. Active extravasation is seen in 41% to 74% cases of PPH on CTA [17] and multiphasic CT, including a noncontrast, arterial, and portal venous phases, has excellent accuracy of 97% [18] for detection of the site of active extravasation, similar to that of gastrointestinal hemorrhage [17,18]. CTA can be falsely positive because of dilated tortuous hypertrophic uterine arteries mimicking extravasation and be falsely negative in atony because of slow intermittent hemorrhage [12,18].


Postpartum Hemorrhage

Postpartum Hemorrhage. Serpiginous myometrial vessels and prominent parametrial vessels can be a sign of VUA [19], whereas the presence of a pseudoaneurysmal sac is a more specific finding [14,20,21]. CTA can also identify and localize the feeding arteries of AVM for treatment planning [14]. However, CTA cannot reliably distinguish acquired VUA from failure of obliteration or subinvolution of the placental bed vessels, assess its severity, or need for intervention [19].


Postpartum Hemorrhage

Postpartum Hemorrhage. MRI Pelvis MRI is not as commonly used in significant life-threatening early PPH as CT, in part related to access and to time required to perform the study in an acute setting. MRI has an important role to play in distinguishing and/or confirming uterine dehiscence versus rupture, in particular when it is confusing on US or CT. RPOC can be seen as a variably enhancing intracavitory mass with variable degree of myometrial thinning [13,14].


Postpartum Hemorrhage

Postpartum Hemorrhage. Patients with difficult vaginal deliveries without large palpable hematomas may benefit from noncontrast MRI to identify deep-seated pelvic hematomas, which, depending on the time since delivery, may demonstrate variable T1 and T2 signal characteristics [14,23]. The superior spatial resolution of MRI compared to US enables localization of hematomas (eg, supralevator versus infralevator location in perivaginal space) for potential targeted intervention [23].


Postpartum Hemorrhage

Postpartum Hemorrhage. VUA can be seen on MRI fast-spin echo sequence as serpiginous signal voids with prominent parametrial vessels, whereas the presence of a pseudoaneurysm sac is more specific [14,20]. Failure of obliteration of the placental bed vessels after pregnancy cannot be reliably distinguished from acquired VUA on MRI [19].


Postpartum Hemorrhage


Postpartum Hemorrhage

Postpartum Hemorrhage. US can detect most pelvic hematomas [13-15]. Rarely, US may demonstrate ovarian vein thrombosis as an echogenic mass within an enlarged ovarian vein [14].


Postpartum Hemorrhage

Postpartum Hemorrhage. Variant 3: Postpartum hemorrhage. Late (greater than 24 hours to 6 weeks) after caesarian delivery. Initial imaging. Secondary or late PPH is typically defined as any significant uterine hemorrhage occurring between 24 hours to 6 weeks postpartum. The most common etiologies are RPOC, subinvolution of the placental bed, or infection. RPOCs are more likely after vaginal delivery, whereas postpartum endometritis is more common after cesarean. Less common causes include, but are not limited to, coagulopathy, pseudoaneurysm or AVMs, dehiscent cesarean scar, or gestational trophoblast disease (GTD). Primary PPH is considered a risk factor for secondary PPH. CT Abdomen and Pelvis In the setting of hemorrhage, the primary role of CT is to determine whether active ongoing hemorrhage is present, to localize the bleeding, and to identify the source, which is best accomplished with a CT with IV contrast. There is little clinical utility in a noncontrast CT or CT with and without IV contrast in the setting of active ongoing hemorrhage. In hemodynamically stable patients, when conventional medical treatment has been unsuccessful in terminating hemorrhage, multiphasic CT can be useful in localizing the source of extravasation for targeted therapy [12,29], particularly in suspected intra-abdominal hemorrhage [12].


Postpartum Hemorrhage

Postpartum Hemorrhage. CT can detect vascular complications such as bladder flap, subfascial, or perivaginal space hematoma and delineate relationship to adjacent organs (supralevator versus infralevator location in the perivaginal space) [14,15]. Small (<4 cm) subfascial and bladder flap hematomas may not be clinically significant [15]. A >5 cm bladder flap hematoma should raise suspicion for uterine dehiscence, characterized by disruption of the endometrial and myometrial layers with an intact serosal layer [15,16]. Low correlation between clinical and radiologic findings of dehiscence have been noted, and it is important not to interpret hypodense edema at the cesarean incision site as dehiscence in the first postpartum week [15]. Presence of gas in the myometrial defect extending from the endometrium to the parametrial tissue along with hemoperitoneum are findings suggestive of uterine rupture [15].


Postpartum Hemorrhage

Postpartum Hemorrhage. RPOC can be difficult to differentiate from blood products even on multiphase CT [12]. Endometritis is a clinical diagnosis with a nonspecific CT appearance of a thickened heterogeneous endometrium with fluid, gas, and debris within the cavity [15]. Superimposed parametrial abscess or infected hematoma and other complications such as ovarian vein thrombosis [14,15] can be detected on CT.


Postpartum Hemorrhage

Postpartum Hemorrhage. GTD (most commonly choriocarcinoma after third trimester delivery) is a rare cause of delayed PPH and appears as a heterogeneous hypervascular intrauterine mass, often with central necrosis, indistinguishable from RPOC, except in cases of invasion of adjacent organs or distant metastasis [14].


Postpartum Hemorrhage

Postpartum Hemorrhage. Serpiginous myometrial vessels and prominent parametrial vessels can be a sign of VUA [19], whereas the presence of a pseudoaneurysmal sac is a more specific finding [14,20,21]. CTA can also identify and localize the feeding arteries of AVM for treatment planning [14]. However, CTA cannot reliably distinguish acquired VUA from failure of obliteration/subinvolution of the placental bed vessels, assess its severity, or need for intervention [19].


Postpartum Hemorrhage

Postpartum Hemorrhage. MRI Pelvis In clinically suspected endometritis, MRI can identify associated findings such as abscess or infected hematoma that may require drainage and other complications such as ovarian vein thrombosis [14]. RPOC can be seen as a variably enhancing intracavitory mass with variable degree of myometrial thinning [13,14]. MRI is superior to CT and US in detecting the myometrial defect with intact serosal layer in uterine dehiscence because of superior soft- tissue contrast [14,15]. However, in the immediate postpartum period, the cesarean section incision can be T1 and T2 hyperintense and may mimic a dehiscence [22].


Postpartum Hemorrhage

Postpartum Hemorrhage. Noncontrast MRI can be used to identify bladder flap, subfascial, and deep-seated pelvic hematomas, which depending on the time since delivery, may demonstrate variable T1 and T2 signal characteristics [14,23] and a low T2 signal rim after >2 weeks due to hemosiderin deposition. The superior spatial resolution of MRI compared to


Postpartum Hemorrhage

Postpartum Hemorrhage


Postpartum Hemorrhage

Postpartum Hemorrhage. US enables localization of hematoma (eg, supralevator versus infralevator location in perivaginal space) for potential targeted intervention [23].


Postpartum Hemorrhage

Postpartum Hemorrhage. GTD is a rare cause of delayed PPH and appears as a heterogeneous hypervascular intrauterine mass, often with central necrosis, indistinguishable from RPOC, except in cases of invasion of adjacent organs or distant metastasis [14].


Postpartum Hemorrhage

Postpartum Hemorrhage. US Duplex Doppler Pelvis Transabdominal US is often performed in conjunction with transvaginal US and color or power Doppler and should be considered a single examination. Color and spectral Doppler are commonly employed in pelvic sonography to detect the presence of vascular flow in normal anatomic structures as well as various pathologic lesions. In women with PPH, Doppler improves the specificity and negative predictive value of detecting RPOC by detecting vascularity within a thickened endometrial echo complex [24]. When a pseudoaneurysm is suspected, color and spectral Doppler can detect swirling or yin-yang pattern of blood flow within a hypoanechoic structure [14,20].


Postpartum Hemorrhage

Postpartum Hemorrhage. Pitfalls in assessment include that absence of vascularity could represent an avascular RPOC [12] and marked vascularity can mimic a pseudoaneurysm, although RPOC generally extends to the endometrium, whereas pseudoaneurysm is restricted to the myometrium [25]. However, it can be difficult to distinguish acquired VUA from subinvolution of the placental bed [19,26] or to assess its severity or need for intervention on US [19]. Although high peak systolic velocities have been used to predict need for intervention, there is considerable overlap [7].


Postpartum Hemorrhage

Postpartum Hemorrhage. US Pelvis Transvaginal Pelvic US using a combined transvaginal and transabdominal approach is the primary modality of choice for the investigation of late PPH as RPOC with or without endometritis is one of the major causes of secondary or late PPH. Although detection of an echogenic or mixed-echo pattern endometrial mass has the highest sensitivity for the detection of RPOC, this is a nonspecific finding that overlaps with the normal postpartum appearance [14,31]. The most specific finding is a vascular echogenic mass, although flow may not be identified in all RPOC. Another US finding in RPOC is a thickened endometrial echo complex with a variable cutoff of 8 to 13 mm [25,32]. US can be used in this setting to assess for coexisting pathology and complications, such as RPOC, hematoma, or abscess.


Postpartum Hemorrhage

Postpartum Hemorrhage. US can detect most pelvic hematomas [13], including bladder flap hematomas [14,15] with superimposed echogenic foci of air suggesting infection [15]. Although uterine scar dehiscence may be seen on US as an irregular thinned uterine wall or a myometrial defect [14], differentiation from the normal appearance of the cesarean section scar can be difficult.


Postpartum Hemorrhage

Postpartum Hemorrhage. VUA, including uterine artery pseudoaneurysms, are a relatively rare cause of PPH [19,20] and most commonly arise from the uterine artery. VUA appear as hypoechoic tortuous channels or masses in the myometrium with turbulent flow on color Doppler and high-velocity and low-resistance flow on spectral analysis.


Postpartum Hemorrhage

Postpartum Hemorrhage. It can be difficult to distinguish acquired VUA from subinvolution of the placental bed [19,26] or to assess its severity or need for intervention on US [19]. A dilated vessel in the myometrium may suggest the diagnosis of pseudoaneurysm.


Postpartum Hemorrhage

Postpartum Hemorrhage

Postpartum Hemorrhage. Postpartum Hemorrhage


Postpartum Hemorrhage

Postpartum Hemorrhage. Variant 4: Postpartum hemorrhage. Late (greater than 24 hours to 6 weeks) after vaginal delivery. Initial imaging. Secondary or late PPH is typically defined as any significant uterine hemorrhage occurring between 24 hours to 6 weeks postpartum. The most common etiologies are RPOC, subinvolution of the placental bed, or infection. RPOC are more likely after vaginal delivery, whereas postpartum endometritis is more common after cesarean. Less common causes include, but are not limited to, coagulopathy, pseudoaneurysm or AVMs, dehiscent cesarean scar, or GTD. Primary PPH is considered a risk factor for secondary PPH. CT Abdomen and Pelvis In the setting of hemorrhage, the primary role of CT is to determine whether active ongoing hemorrhage is present, to localize the bleeding, and to identify the source, which is best accomplished with a CT with IV contrast. There is little clinical utility in a noncontrast CT or CT with and without IV contrast in the setting of active ongoing hemorrhage. In hemodynamically stable patients with delayed PPH, multiphasic CTA can be useful in localizing the source of extravasation for targeted therapy [12,29], particularly in suspected intra-abdominal hemorrhage [12].


Postpartum Hemorrhage

Postpartum Hemorrhage. CT can detect vascular complications such as supraumbilical and perivaginal space hematoma and delineate the relationship to adjacent organs (supralevator versus infralevator location in the perivaginal space) [12,14,15]. Although the diagnosis of complete uterine inversion is made clinically, subacute partial uterine inversions may be detected as a concavity of the uterine fundus in CT [12].


Postpartum Hemorrhage


Postpartum Hemorrhage

Postpartum Hemorrhage. CTA Abdomen and Pelvis Persistent hemorrhage after empiric embolization is an indication for CTA [12]. Active extravasation is seen in 41% to 74% cases of PPH on CTA [17] and multiphasic CT, including a noncontrast, arterial, and portal venous phases, has excellent accuracy of 97% [18] for detection of the site of active extravasation, similar to that of gastrointestinal hemorrhage [17,18]. CTA can be falsely positive because of dilated tortuous hypertrophic uterine arteries mimicking extravasation and be falsely negative in atony because of slow intermittent hemorrhage [12,18].


Postpartum Hemorrhage

Postpartum Hemorrhage. MRI Pelvis In clinically suspected endometritis, MRI can identify associated findings such as abscess or infected hematoma that may require drainage and other complications such as ovarian vein thrombosis [14]. RPOC can be seen as a variably enhancing intracavitory mass with variable degree of myometrial thinning [13,14].


Postpartum Hemorrhage

Postpartum Hemorrhage. Patients with difficult vaginal delivery without large palpable hematoma may benefit from noncontrast MRI to identify deep-seated pelvic hematomas, which depending on the time since delivery may demonstrate variable T1 and T2 signal characteristics [14,23] and a low T2 signal rim after >2 weeks because of hemosiderin deposition. The superior spatial resolution of MRI compared to US enables localization of hematoma (eg, supralevator versus infralevator location in perivaginal space) for potential targeted intervention [23].


Postpartum Hemorrhage

Postpartum Hemorrhage. VUA can be seen on MRI fast-spin echo sequence as serpiginous signal voids with prominent parametrial vessels, whereas the presence of a pseudoaneurysm sac is more specific [14,20]. Failure of obliteration of the placental bed vessels after pregnancy cannot be reliably distinguished from acquired VUA on MRI [19].


Postpartum Hemorrhage

Postpartum Hemorrhage


Postpartum Hemorrhage

Postpartum Hemorrhage. Pitfalls in assessment include that absence of vascularity could represent an avascular RPOC [12], and marked vascularity can mimic a pseudoaneurysm, although RPOC generally extends to the endometrium, whereas pseudoaneurysm is restricted to the myometrium [25]. However, it can be difficult to distinguish acquired VUA from subinvolution of the placental bed [19,26] or to assess its severity or need for intervention on US [19]. Although high peak systolic velocities have been used to predict need for intervention, there is considerable overlap [7].


Postpartum Hemorrhage

Postpartum Hemorrhage. US Pelvis Transvaginal A combined transabdominal and transvaginal approach is the primary modality of choice as RPOC with or without endometritis is one of the major causes of secondary or late PPH. Although transvaginal US detection of an echogenic endometrial mass has the highest sensitivity for the detection of RPOC, this is a nonspecific finding that can overlap with the normal postpartum appearance [14,31]. Another US finding in RPOC is a thickened endometrial echo complex with a variable cutoff of 8 to 13 mm [25,32]. Endometritis, on the other hand, is a clinical diagnosis that has a nonspecific US appearance of a thick heterogeneous endometrium, with fluid and air within the cavity [14,33,34]. US can be used in this setting to assess for coexisting pathology and complications, such as RPOC, hematoma, or abscess. US can detect most pelvic hematomas [13-15] with superimposed echogenic foci of air suggesting infection [15].


Postpartum Hemorrhage

Postpartum Hemorrhage. Supporting Documents The evidence table, literature search, and appendix for this topic are available at https://acsearch.acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation.


Postpartum Hemorrhage

Postpartum Hemorrhage. For additional information on the Appropriateness Criteria methodology and other supporting documents go to www.acr.org/ac.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Introduction/Background According to the American Cancer Society, approximately 73,750 new cases of kidney and renal pelvis cancer will be diagnosed in the United States in 2020, and approximately 14,830 people will die of this disease [1]. Renal cell carcinoma (RCC) accounts for 85% of all malignant renal tumors and represents approximately 2% to 3% of all malignancies in adults [2]. RCC is also considered the most lethal of all urologic cancers.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Surgical resection with curative intent, including radical nephrectomy (RN) or partial nephrectomy (PN), continues to be the standard of care for clinically localized RCC [2]. Ablative therapies such as radiofrequency ablation, microwave ablation, and cryoablation have been shown to be effective and safe alternatives for the treatment of small localized RCCs [3-7]. In some patients with small localized RCCs, treatment may also be deferred, with management instead consisting of active surveillance protocols [8].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. For follow-up of patients with treated or untreated RCC and those with neoplasms suspected to represent RCC, radiologic imaging is the most useful component of surveillance, because most relapses and cases of disease progression are identified when patients are asymptomatic [9,10]. There is currently no consensus regarding surveillance protocols; however, various guidelines and strategies have been developed by international oncologic and urologic societies, such as the National Comprehensive Cancer Network, the American Urological Association, and the European Association of Urology, using both patient- and tumor-specific characteristics [2,9,11,12]. Although imaging is the centerpiece in all of these guidelines, the recommendations vary regarding the timing, frequency, and duration of follow-up, as well as the selection of imaging modalities for follow-up [12,13]. Understanding the strengths and limitations of the various imaging modalities for the detection of disease recurrence or progression is important when planning follow-up regimens.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. In this document, we provide an update on the appropriate use of imaging examinations for asymptomatic patients who have been treated for RCC with RN, PN, or ablative therapies. We also address the appropriate imaging examinations for asymptomatic patients with localized biopsy-proven or suspected RCC who are undergoing active surveillance. As in the previous version, this document does not address the imaging of complications from treatment and does not discuss the follow-up of patients with known residual or recurrent cancer.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Special Imaging Considerations CT urography (CTU) is an imaging study that is tailored to improve visualization of both the upper and lower urinary tracts. There is variability in the specific parameters, but it usually involves unenhanced images followed by intravenous (IV) contrast-enhanced images, including nephrographic and excretory phases acquired at least 5 minutes after contrast injection. Alternatively, a split-bolus technique uses an initial loading dose of IV contrast and then obtains a combined nephrographic-excretory phase after a second IV contrast dose; some sites include arterial phase. CTU should use thin-slice acquisition. Reconstruction methods commonly include maximum intensity projection or 3-D volume rendering. For the purposes of this document, we make a distinction between CTU and CT abdomen and pelvis without and with IV contrast. CT abdomen and pelvis without and with IV contrast is


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Reprint requests to: publications@acr.org


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma defined as any protocol not specifically tailored for evaluation of the upper and lower urinary tracts and without both the precontrast and excretory phases.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MR urography (MRU) is also tailored to improve imaging of the urinary system. Unenhanced MRU relies upon heavily T2-weighted imaging of the intrinsic high signal intensity from urine for evaluation of the urinary tract. IV contrast is administered to provide additional information regarding obstruction, urothelial thickening, focal lesions, and stones. A contrast-enhanced T1-weighted series should include a corticomedullary, nephrographic, and excretory phase. Thin-slice acquisition and multiplanar imaging should be obtained. For the purposes of this document, we make a distinction between MRU and MRI abdomen and pelvis without and with IV contrast. MRI abdomen and pelvis without and with IV contrast is defined as any protocol not specifically tailored for evaluation of the upper and lower urinary tracts, without both the precontrast and excretory phases, and without heavily T2- weighted images of the urinary tract.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Discussion of Procedures by Variant Variant 1: Follow-up for clinically localized renal cell carcinoma; post radical or partial nephrectomy. Many tumor- and patient-specific characteristics have been shown to be predictive of local recurrence or distant metastasis of RCC after treatment [2,14-19]. In addition to these characteristics, the timing and location of tumor recurrence and the type of treatment (ie, RN versus PN) are considered in the development of imaging surveillance strategies that aim to identify asymptomatic solitary or oligometastatic disease that may benefit from early potentially curative or life-prolonging salvage treatment [10,16,20].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Among the tumor characteristics predictive of tumor recurrence, the tumor, node, and metastases staging system has been the most extensively researched; associations between pathologic T stage and both the risk and patterns of tumor recurrence have been demonstrated in many studies [14,15,17,21]. Patient symptoms, tumor size, tumor necrosis, and microvascular invasion are some of the other factors that have been evaluated and integrated into risk stratification models that separate patients into low-, intermediate-, or high-risk groups according to the probability of local recurrence or distant metastases [11,14,18,19]. Most recurrences occur within 3 years after treatment, with a median time to relapse of 1 to 2 years; thus, most surveillance guidelines address follow-up for up to 5 years after treatment [2,9,11,22]. In patients with high-risk tumors (ie, pT2 and pT3 tumors), especially those patients without a significant competing risk for non-RCC death, follow-up beyond 5 years may also be considered because of a nonnegligible incidence of late recurrence [14,18].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Patients who have undergone PN have a similar or slightly higher incidence of local recurrence compared with those who have undergone RN [11,23]. In some guidelines, a more rigorous follow-up protocol is recommended to assess for local recurrence in those who have undergone PN [2,9]. However, more commonly, recurrence manifests as distant metastases [10,20,24,25]. The lungs are the most common site affected by metastases, followed by the lymph nodes, bones, liver, adrenal glands, and brain. Other less common sites include the spleen, pancreas, diaphragm, heart, skin, and connective tissues. Apart from bone and brain metastases, most metastases and local recurrences are identified in asymptomatic patients [10,15,18,26].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma Radiography Chest A chest radiograph is a low-yield diagnostic tool for detecting pulmonary metastasis in patients after surgical excision of RCC, particularly in those with low-risk tumors, irrespective of the treatment modality (RN, PN, or ablation) [27,28]. In a retrospective analysis of 221 patients with pT1-3N0M0 RCC, only 0.85% of the follow-up chest radiographs detected pulmonary metastases in asymptomatic patients [28]. The yield of a chest radiograph increased to 1.9% when used in patients with intermediate-risk (T2) or high-risk (T3) tumors. In more than half of the patients, pulmonary metastases were detected when patients became symptomatic outside of the routine follow- up. In a second retrospective analysis of 258 patients who had undergone resection or ablation for low-risk (T1a) RCC, pulmonary metastases developed in 3 patients (1.2%), but in only 1 patient (0.4%) was this metastasis diagnosed with surveillance chest radiographs [27]. In a more recent study, only 2 of 384 patients (0.005%) with T1a RCC were found to have pulmonary metastases after surgical therapy, and in both cases, the pulmonary metastases were not detected by surveillance chest radiographs [24]. In the same study, 10 of 184 patients (5.4%) with T1b RCC had suspicious pulmonary lesions found on surveillance radiography of the chest; only 2 of these patients had biopsy-confirmed pulmonary metastasis. However, according to guidelines from urologic and oncologic societies, a chest radiograph is still the recommended technique for the surveillance of patients with T1a tumors, and this technique is also recommended as an alternative to chest CT for the surveillance of patients with T2 and T3 tumors after an initial negative follow-up chest CT examination [9,11]. This is in part because of concerns about potential false-positive findings with chest CT (ie, intrapulmonary lymph nodes and granulomas) that can lead to further unnecessary and potentially invasive investigations [9,12].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Abdomen There is no relevant literature regarding the use of abdominal radiographs in the follow-up of patients after surgical excision of RCC, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Skeletal Survey There is no relevant literature regarding the use of a radiographic survey of the whole body in the follow-up of patients after surgical excision of RCC, and this method is not included in the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Intravenous Urography There is no relevant literature regarding the use of IV urography in the follow-up of patients after surgical excision of RCC, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CT Abdomen CT of the abdomen is the most commonly used method for surveillance after surgical excision of RCC [29]. CT is a sensitive method for the detection of recurrences in the resection bed and in other more common sites of metastases in the abdomen, such as the contralateral kidney, adrenal glands, liver, and lymph nodes, and in the visualized bones [16,17,20,22,30]. Although several studies have advised against routine imaging of the abdomen after resection of low-risk (T1) tumors because of the low frequency of abdominal recurrences [15,17,21,30], CT of the abdomen is commonly performed in this group, particularly after PN, to serve as a baseline for future comparisons and to evaluate postoperative complications [9]. Although CT of the abdomen performed without and with IV contrast may be considered beneficial in cases in which postoperative changes need to be distinguished from residual or recurrent tumors, in general, surveillance protocols in oncology often use a single-phase examination in the portal- venous phase. Because RCC metastases tend to be hypervascular, some authors have also suggested that arterial phase imaging can be used to complement portal-venous imaging for the detection of RCC metastases to the liver, pancreas, and contralateral kidney. In a retrospective study including 100 patients, 9 patients had metastases in the liver, pancreas, or contralateral kidney detected only in the arterial phase, and these findings led to a change in management for 2 patients [31]. For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), CT of the abdomen without IV contrast may be considered appropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CT Abdomen and Pelvis CT of the abdomen is the most commonly used method for surveillance after surgical excision of RCC [29]. CT is a sensitive method for the detection of recurrences in the resection bed and in other more common sites of metastases in the abdomen, such as the contralateral kidney, adrenal glands, liver, and lymph nodes, and in the visualized bones [16,17,20,22,30]. Although several studies have advised against routine imaging of the abdomen after resection of


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. 6 Post-treatment Follow-up of Renal Cell Carcinoma


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. low-risk (T1) tumors because of the low frequency of abdominal recurrences [15,17,21,30], CT of the abdomen is commonly performed in this group, particularly after PN, to serve as a baseline for future comparisons and to evaluate postoperative complications [9]. Although CT of the abdomen performed without and with IV contrast may be considered beneficial in cases in which postoperative changes need to be distinguished from residual or recurrent tumors, in general, surveillance protocols in oncology often use a single-phase examination in the portal- venous phase. Because RCC metastases tend to be hypervascular, some authors have also suggested that arterial phase imaging can be used to complement portal-venous imaging for the detection of RCC metastases to the liver, pancreas, and contralateral kidney. In a retrospective study including 100 patients, 9 patients had metastases in the liver, pancreas, or contralateral kidney detected only in the arterial phase, and these findings led to a change in management for 2 patients [31]. For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), CT of the abdomen without IV contrast may be considered appropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CTU There is no relevant literature suggesting that CTU offers any additional benefit over conventional CT of the abdomen in the surveillance of patients after treatment of localized RCC, and this method is not included in the guidelines [2,9,11]. In a retrospective analysis of 23 tumors that progressed locally after ablation, CT or MRIs obtained in the corticomedullary phase were found to be sufficient for diagnosis of recurrence in 100% of the cases; noncontrast, nephrographic, and excretory-phase images, which are typically obtained in a CTU or MRU protocol, were able to detect recurrence in only 11%, 81%, and 44% of cases, respectively [35].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CT Chest Limited data suggest that CT is more sensitive than radiography for the detection of pulmonary metastases from RCC during staging [27]. Although no direct comparison between the 2 methods has been reported in the posttreatment surveillance setting, one study demonstrated that the overwhelming majority of chest recurrences in asymptomatic cases are detected by chest CT examinations (92.3%) rather than by radiography (7.7%) [36]. In addition to a high sensitivity for the detection of pulmonary metastases, chest CT has a high sensitivity for the detection of intrathoracic nodal metastases from RCC; this finding has prognostic implications and may affect surgical planning for metastases resection [37]. The use of IV contrast is optional for chest CT, but it may be beneficial for the detection and characterization of hilar lymph nodes. In patients undergoing surveillance with CT of the abdomen with IV contrast, chest CT should also be performed after IV contrast administration.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Unlike CT of the abdomen, in which images obtained without and with IV contrast may be appropriate in some circumstances, CT of the chest without and with IV contrast does not provide additional information in these patients and is considered inappropriate. Although some consider CT to be the standard chest imaging technique for surveillance after RCC resection [11], there are concerns regarding the risk of false-positive findings (ie, intrapulmonary lymph nodes and granulomas), particularly in patients with T1a RCC, which can lead to further unnecessary and potentially invasive investigations [9]. It is worth noting that in a recent pilot study, the authors suggested that CT of the chest may not be necessary to identify most cases of pulmonary recurrence when a CT examination of the abdomen with coverage of the lung bases to the T7 thoracic level is performed [26].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CT Head Most patients with metastases to the central nervous system are symptomatic. Thus, surveillance protocols after surgical excision of RCC have not supported routine imaging of the brain to search for metastases in asymptomatic patients. Brain imaging should be performed only in cases with suggestive signs or symptoms [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma MRI Abdomen MRI of the abdomen without and with IV contrast is considered in all major guidelines as an adequate method for surveillance of the abdomen after surgical excision of RCC [2,9,11]. MRI has a high soft-tissue contrast resolution and is an accurate method for detecting metastases in the common sites of RCC recurrences (ie, liver, adrenal glands, lymph nodes, contralateral kidney, and bones) [38]. MRI can also assist in the distinction between residual/recurrent disease and postoperative changes after PN [39]. For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), MRI of the abdomen without IV contrast may be considered appropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRI Abdomen and Pelvis MRI of the abdomen without and with IV contrast is considered in all major guidelines as an adequate method for surveillance of the abdomen after surgical excision of RCC [2,9,11]. MRI has a high soft-tissue contrast resolution and is an accurate method for detecting metastases in the common sites of RCC recurrences (ie, liver, adrenal glands, lymph nodes, contralateral kidney, and bones) [38]. MRI can also assist in the distinction between residual/recurrent disease and postoperative changes after PN [39]. For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), MRI of the abdomen without IV contrast may be considered appropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Although MRI of the abdomen with IV contrast is considered in all major guidelines as an adequate method for surveillance of the abdomen after surgical excision of RCC, imaging the pelvis during surveillance after RCC treatment is considered optional in the guidelines [2,9,11]. There is no relevant literature regarding the use of MRI of the pelvis in the follow-up of patients after surgical excision of RCC, although data from 2 retrospective studies suggested that imaging of the pelvis with CT had minimal benefit for the detection of metastases in patients after RN or PN for RCC [25,32-34]. Therefore, MRI of the abdomen alone may be preferred over MRI of the abdomen and pelvis in this setting.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRU There is no relevant literature suggesting that MRU offers any additional benefit over conventional MRI of the abdomen in the surveillance of patients after treatment of localized RCC, and this method is not included in the guidelines [2,9,11]. In a retrospective analysis of 23 tumors that progressed locally after ablation, CT or MRIs obtained in the corticomedullary phase were found to be sufficient for diagnosis of recurrence in 100% of the cases; noncontrast, nephrographic, and excretory-phase images, which are typically obtained in a CTU or MRU protocol, were able to detect recurrence in only 11%, 81%, and 44% of cases, respectively [35].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRI Head Most patients with metastases to the central nervous system are symptomatic. Thus, surveillance protocols for RCC have not supported routine imaging of the brain to search for metastases in asymptomatic patients. Brain imaging should be performed only in cases with suggestive signs or symptoms [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. US Kidney Retroperitoneal The major guidelines include US as another option for imaging surveillance of the abdomen after surgical resection of localized RCC [2,9,11]. Although US may be considered an appropriate alternative for patients with contraindications to CT or MRI, one important consideration is that US is likely to be less sensitive than CT or MRI for the detection of small recurrences or distant visceral and nodal metastases in the abdomen. In one study, among 14 patients who were found to have recurrence after RN or PN for T1-3 RCC, US correctly identified only 1 case of recurrence, whereas CT detected all cases of recurrence [40]. US failed to detect 4 out of 5 recurrences in the kidney after PN [40]. In another study investigating outcomes after PN for T1-2 RCC, CT/MRI detected 96.6% of recurrences in the abdomen, whereas US detected only 3.4% of abdominal recurrences [36].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. US Abdomen with IV Contrast There is no relevant literature regarding the use of contrast-enhanced US (CEUS) in the follow-up of patients after surgical excision of RCC, and this method is not included in the guidelines [2,9,11]. Studies evaluating the performance of CEUS after ablative treatment of renal masses have shown that CEUS has an excellent concordance with CT or MRI with regard to the presence or absence of residual or recurrent tumor after ablation, both immediately after treatment and through long-term follow-up [41-49]. One important consideration is that CEUS would still be less sensitive than CT or MRI for the detection of distant visceral and nodal metastases because the contrast-enhanced portion of the study would be limited to the surgical bed. Nevertheless, in patients at low risk for recurrence, CEUS may be considered an appropriate alternative to CT and MRI.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma Bone Scan Whole Body The prevalence of osseous metastases after treatment for localized RCC has been shown to be low in patients without symptoms (ie, bone pain) or without laboratory abnormalities suggestive of osseous metastases (ie, elevated serum alkaline phosphatase level) [50,51]. Furthermore, the sites commonly involved by osseous metastases, such as the thoracolumbar spine and ribs, are located in areas covered by chest and abdominal imaging. Thus, even though bone scanning can be helpful to confirm clinically or radiographically suspected metastatic disease, current guidelines do not support its routine use in surveillance after treatment for localized RCC [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Preliminary results for other PET tracers are also becoming available. For instance, in a prospective study of 28 patients with RCC undergoing initial staging or restaging, 11C-choline PET/CT was significantly more accurate than FDG-PET/CT (85.7% versus 57.1%). Among 120 lesions detected, 11C-choline PET/CT detected 75 lesions (62.5%), whereas FDG-PET/CT detected 47 lesions (39.2%) [54]. In another prospective study of 10 patients with metastatic RCC, 18F-sodium fluoride (NaF) PET/CT was found to be significantly more sensitive for the detection of RCC skeletal metastases than Tc-99m bone scintigraphy or CT, with sensitivities of 100%, 29%, and 46%, respectively. CT and Tc-99m bone scintigraphy in this study identified only 65% of the metastases detected by NaF-PET/CT [55]. A small series has also shown that 68Ga-labeled prostate-specific membrane antigen PET/CT can help to detect metastatic lesions in patients with the clear cell subtype of RCC [56].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Variant 2: Follow-up for clinically localized renal cell carcinoma; post ablation. Among several techniques available for the ablation of localized RCC, thermal ablation techniques using radiofrequency ablation, microwave ablation, or cryoablation are the most commonly used; these procedures can be performed percutaneously or laparoscopically [57-59]. Ablation therapy is currently considered a less invasive alternative to RN or PN for renal masses measuring <4 cm (ie, T1a tumors) [2,9,11]. There is growing evidence suggesting that ablation of small renal masses produces oncologic outcomes that approach those of surgical excision but with a significantly lower overall complication rate and a significantly lower decline in renal function [5- 7,57,60-67]. Because of the higher rate of local recurrence seen with ablation than with surgical excision, ablation requires more frequent use of imaging to monitor tumor involution over time [3,29,65]. Early detection of treatment failure or recurrence is important to maximize retreatment potential [65,68]. Because the risk of local recurrence is greater than the risk of distant metastases in this patient population, surveillance strategies should prioritize evaluation of the treatment bed. Guidelines recommend performing CT or MRI of the abdomen at 3 and 6 months after ablation and yearly thereafter for 5 years [2,9,11]. Guidelines also recommend the use of imaging surveillance with chest radiography or CT annually for up to 5 years after ablation of RCC [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Imaging-guided biopsy of renal masses is encouraged in patients considering ablative therapies [2,9,11,60]. Pretreatment biopsy can help confirm the malignant nature and aggressiveness of the tumors, which in turn can influence the frequency and duration of follow-up. After treatment, biopsy is also indicated for masses that fail to regress or that display findings suggestive of recurrence.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Chest Chest radiography is a low-yield diagnostic tool for detecting pulmonary metastasis in patients treated for RCC, particularly in those with low-risk tumors, irrespective of the treatment modality (RN, PN, or ablation) [27,28]. In a retrospective analysis of 258 patients who had undergone resection or ablation of low-risk (T1a) RCC, pulmonary metastases developed in 3 patients (1.2%), but in only 1 patient (0.4%) was this metastasis diagnosed by surveillance chest radiographs [27]. However, according to guidelines from urologic and oncologic societies, chest radiography


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma is the recommended technique for surveillance of patients after ablation of T1a tumors [2,9,11]. This is in part because of concerns about potential false-positive findings with chest CT (ie, intrapulmonary lymph nodes and granulomas) that can lead to further unnecessary and potentially invasive investigations [9,12].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Abdomen There is no relevant literature regarding the use of abdominal radiographs in the follow-up of patients after localized RCC ablation, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Skeletal Survey There is no relevant literature regarding the use of a radiographic survey of the whole body in the follow-up of patients after localized RCC ablation, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Intravenous Urography There is no relevant literature regarding the use of IV urography in the follow-up of patients after localized RCC ablation, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Imaging of the pelvis with CT has been found to have limited benefit for the detection of metastases in initial staging and after RN or PN for RCC [25,32-34] and is considered optional in the surveillance guidelines [2,9,11]. Because the risk of distant metastases is significantly lower in patients with localized RCC after ablation, CT of the abdomen is preferred over CT of the abdomen and pelvis.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma CT Chest Limited data suggest that CT is more sensitive than radiography for the detection of pulmonary metastases from RCC during staging [27]. Although no direct comparison between the 2 methods has been reported in the posttreatment surveillance setting, one study demonstrated that the overwhelming majority of chest recurrences in asymptomatic cases are detected by chest CT examinations (92.3%) rather than by radiography (7.7%) [36]. In addition to a high sensitivity for the detection of pulmonary metastases, chest CT has a high sensitivity for the detection of intrathoracic nodal metastases from RCC; this finding has prognostic implications and may affect surgical planning for metastases resection [37]. The use of IV contrast is optional for chest CT, but it may be beneficial for the detection and characterization of hilar lymph nodes. In patients undergoing surveillance with CT of the abdomen with IV contrast, chest CT should also be performed after IV contrast administration.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Unlike CT of the abdomen, in which images without and with IV contrast are appropriate, CT of the chest without and with IV contrast does not provide additional information in these patients and is considered inappropriate. Although some consider CT the standard chest imaging technique for surveillance after RCC resection [11], there are concerns about the risk of false-positive findings (ie, intrapulmonary lymph nodes and granulomas), particularly in patients with T1a RCC, which can lead to further unnecessary and potentially invasive investigations [9]. Additionally, some authors suggest that CT of the chest may not be necessary to identify most patients with pulmonary recurrence when CT of the abdomen with coverage of the lung bases at the T7 thoracic level is performed [26].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CT Head Most patients with metastases to the central nervous system are symptomatic. Thus, surveillance protocols after localized RCC ablation have not supported routine imaging of the brain to search for metastases in asymptomatic patients. Brain imaging should be performed only in cases with suggestive signs or symptoms [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CTU There is no relevant literature suggesting that CTU offers any additional benefit over conventional CT of the abdomen in the surveillance of patients after treatment of localized RCC, and this method is not included in the guidelines [2,9,11]. In a retrospective analysis of 23 tumors that progressed locally after ablation, CT or MR images in the corticomedullary phase were found to be sufficient for diagnosis of recurrence in 100% of the cases; noncontrast, nephrographic, and excretory-phase images, which are typically obtained in a CTU or MRU protocol, were able to detect recurrence in only 11%, 81%, and 44% of cases, respectively [35].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRI Abdomen MRI of the abdomen is commonly used for follow-up after ablation of localized RCC [29]. MRI should be performed without and with IV contrast to assess tumor enhancement. Image data sets generated from subtraction of the precontrast from the postcontrast images can assist with evaluation of residual or recurrent tumor enhancement, especially during the first year of follow-up, because of the high signal intensity background of the ablated tumor on T1-weighted images [72]. However, as with CT, persistent tumor enhancement is common after successful ablation, particularly in patients with clear-cell RCC [73], and this enhancement can last for days to months after treatment [72-74]. For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), MRI of the abdomen without IV contrast may be considered appropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRI Abdomen and Pelvis MRI of the abdomen is commonly used for follow-up after ablation of localized RCC [29]. MRI should be performed without and with IV contrast to assess tumor enhancement. Image data sets generated from subtraction of the precontrast from the postcontrast images can assist with evaluation of residual or recurrent tumor enhancement, especially during the first year of follow-up, because of the high signal intensity background of the ablated tumor on T1-weighted images [72]. However, as with CT, persistent tumor enhancement is common after successful ablation, particularly in patients with clear-cell RCC [73], and this enhancement can last for days to months after treatment [72-74]. For patients in whom contrast is contraindicated (eg, previous anaphylactic reactions), MRI of the abdomen without IV contrast may be considered appropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. There is no relevant literature regarding the use of MRI of the pelvis in the follow-up of patients after RCC ablation. Imaging of the pelvis with CT has been found to provide minimal benefit for the detection of metastases in the initial staging and after RN or PN for RCC [25,32-34] and is considered optional in the surveillance guidelines [2,9,11]. Because the risk of distant metastases is significantly lower in patients with localized RCC after ablation, MRI of the abdomen is preferred over MRI of the abdomen and pelvis.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma MRU There is no relevant literature suggesting that MRU offers any additional benefit over conventional MRI of the abdomen in the surveillance of patients after treatment of localized RCC, and this method is not included in the guidelines [2,9,11]. In a retrospective analysis of 23 tumors that progressed locally after ablation, CT or MR images obtained in the corticomedullary phase were found to be sufficient for diagnosis of recurrence in 100% of the cases; noncontrast, nephrographic, and excretory-phase images, which are typically obtained in a CTU or MRU protocol, were able to detect recurrence in only 11%, 81%, and 44% of cases, respectively [35].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRI Head Most patients with metastases to the central nervous system are symptomatic. Thus, surveillance protocols for RCC have not supported routine imaging of the brain to search for metastases in asymptomatic patients. Brain imaging should be performed only in cases with suggestive signs or symptoms [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. US Kidney Retroperitoneal There is no relevant literature regarding the use of conventional US of the kidney in follow-up of patients after localized RCC ablation, and the guidelines offer different recommendations. The National Comprehensive Cancer Network considers US an alternative for annual surveillance after negative evaluation with CT or MRI in the first 6 months [2]; the European Association of Urology recommends US only for surveillance after the treatment of RCC with a low-risk profile [11]; and the American Urological Association does not include US in their recommendations regarding follow-up after ablation [9].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Bone Scan Whole Body The prevalence of osseous metastases has been shown to be low in patients without symptoms (ie, bone pain) or without laboratory abnormalities suggestive of osseous metastases (ie, elevated serum alkaline phosphatase level) [50,51]. Furthermore, the sites commonly involved by osseous metastases, such as the thoracolumbar spine and ribs, are located in areas covered by chest and abdominal imaging. Thus, although Tc-99m bone scanning can be helpful in confirming clinically or radiographically suspected metastatic disease, current guidelines do not support its routine use in surveillance after treatment for localized RCC [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. FDG-PET/CT Skull Base to Mid-Thigh There is no relevant literature regarding the use of FDG-PET or PET/CT for the follow-up of patients after localized RCC ablation. At present, the guidelines do not recommend FDG-PET/CT for the surveillance of patients after RCC ablation [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Variant 3: Follow-up for clinically localized renal cell carcinoma; active surveillance. Active surveillance has been increasingly used for the management of small localized renal masses in a selected group of patients with comorbidities or reduced life expectancy in whom the risks associated with surgical excision or ablative therapies surpass the risk of significant disease progression and cancer-specific mortality [2,9,11,75-80].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Current guidelines recommend biopsy of the renal masses to define the surveillance strategy [2,9,11]. Researchers have found that biopsy is being increasingly used for T1a tumors and that patients who undergo biopsy are significantly more likely to be treated with nonsurgical management (36.8%) than those who do not undergo biopsy (11.4%) [85]. Of note, small renal mass growth kinetics can vary greatly, especially during the initial 6 to 12 months of active surveillance [82,84]. In a systematic review of the literature, researchers found no significant difference between the growth rates of benign masses (0.3 cm/y) and those of malignant masses (0.35 cm/y) [82]. Furthermore, studies have shown that even masses without growth may be malignant [8,76,77,81]. In spite of this, growth rates are generally accepted as surrogates for aggressive behavior and metastatic potential in small renal masses [76,81]. Therefore, the guidelines recommend defining the growth rate of renal masses with serial imaging of the abdomen with CT or MRI within 6 months of the initiation of active surveillance for masses that are shown to be RCCs or oncocytic neoplasms and for those with indeterminate histology features [2,9]. Imaging should be performed at least annually thereafter with CT, MRI, or US. Imaging surveillance of the chest on a yearly basis (or more frequently depending on clinical behavior) is recommended only in those patients with RCC or tumors with oncocytic features [2,9].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Chest Metastatic progression occurs infrequently in patients with T1a renal masses on active surveillance [76,77,81]. Nevertheless, it has been reported that 20% to 30% of T1a tumors have potentially aggressive histologic features, thus requiring surveillance of the chest [9]. No studies have compared chest radiography and chest CT in the setting of active surveillance; however, chest radiography is the most commonly used method for surveillance [2,9]. This is in part because of concerns about potential false-positive findings with chest CT (ie, intrapulmonary lymph nodes and granulomas) that can lead to further unnecessary and potentially invasive investigations [9,12].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Abdomen There is no relevant literature regarding the use of abdominal radiographs in the surveillance of small localized renal masses, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Skeletal Survey There is no relevant literature regarding the use of a radiographic survey of the whole body in the surveillance of small localized renal masses, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Radiography Intravenous Urography There is no relevant literature regarding the use of IV urography in the surveillance of small localized renal masses, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CT Abdomen and Pelvis CT of the abdomen is the most common method by which small renal masses are detected and is also the most commonly used method for surveillance of small localized renal masses. CT of the abdomen performed without


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Although CT of the abdomen is the most commonly used method for surveillance of small localized renal masses, the benefit of imaging the pelvis during surveillance has not yet been defined and is considered optional in the guidelines [2,9,11]. Data from 2 retrospective studies evaluating RCC staging with CT suggested that imaging of the pelvis had limited benefit for the detection of metastases [33,34]. Because metastatic progression occurs infrequently in patients on active surveillance with T1a renal masses [8,75-78,81-84], CT of the abdomen is preferred over CT of the abdomen and pelvis.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CTU There is no relevant literature regarding the use of CTU in the surveillance of small localized renal masses, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CT Chest Chest CT is listed as an alternative to radiography for surveillance of small localized renal masses by the National Comprehensive Cancer Network guidelines [2]. Limited data have demonstrated that CT is more sensitive than radiography for the detection of pulmonary metastases from RCC during staging [27]. However, no comparison between radiography and CT has been reported in the active surveillance setting. Despite the higher sensitivity of CT, there are some concerns about the risk of false-positive findings (ie, intrapulmonary lymph nodes and granulomas), particularly in patients with T1a RCC, which can lead to further unnecessary and potentially invasive investigations [9]. Additionally, some authors suggest that CT of the chest may not be necessary to identify most cases of pulmonary recurrence after nephrectomy for RCC when CT of the abdomen with coverage of the lung bases at the T7 thoracic level is performed [26]. The use of IV contrast is optional for CT of the chest but it may be beneficial for detection and characterization of the hilar lymph nodes. In patients undergoing active surveillance with CT of the abdomen who are receiving IV contrast, chest CT can also be performed after IV contrast administration. Unlike CT of the abdomen, in which images without and with IV contrast may be appropriate in some circumstances, CT of the chest without and with IV contrast does not provide additional information in these patients and is considered inappropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. CT Head Most patients with metastases to the central nervous system are symptomatic. Thus, active surveillance protocols for small localized renal masses have not supported routine imaging of the brain to search for metastases in asymptomatic patients. Brain imaging should be performed only in cases with suggestive signs or symptoms [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRI Abdomen MRI of the abdomen without and with IV contrast is an accurate method for the detection and characterization of small localized renal masses. Different sequences, including T2-weighted, chemical shift T1-weighted, contrast- enhanced T1-weighted, and diffusion-weighted images, can help distinguish RCC from other benign and malignant lesions and distinguish the clear-cell subtype from other subtypes of RCC. Some MRI features of renal masses beyond size and growth rates can also be used to determine tumor aggressiveness and risk of metastatic potential [87]. This may be particularly useful for the characterization of small renal masses that have indeterminate findings on CT and US or when biopsy of these masses is not feasible or is inconclusive. Active surveillance guidelines include MRI and CT as appropriate imaging modalities for the initial evaluation of growth patterns and for subsequent follow-up [2,9,11]. For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), MRI of the abdomen without IV contrast may be considered appropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Post-treatment Follow-up of Renal Cell Carcinoma MRI Abdomen and Pelvis MRI of the abdomen without and with IV contrast is an accurate method for the detection and characterization of small localized renal masses. Different sequences, including T2-weighted, chemical shift T1-weighted, contrast- enhanced T1-weighted, and diffusion-weighted images, can help distinguish RCC from other benign and malignant lesions and distinguish the clear-cell subtype from other subtypes of RCC. Some MRI features of renal masses beyond size and growth rates can also be used to determine tumor aggressiveness and risk of metastatic potential [87]. This may be particularly useful for the characterization of small renal masses that have indeterminate findings on CT and US or when biopsy of these masses is not feasible or is inconclusive. Active surveillance guidelines include MRI and CT as appropriate imaging modalities for the initial evaluation of growth patterns and for subsequent follow-up [2,9,11]. For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), MRI of the abdomen without IV contrast may be considered appropriate.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Although MRI of the abdomen can be useful for characterization and follow-up of small localized renal masses undergoing active surveillance, the benefit of imaging the pelvis during surveillance has not yet been defined and is considered optional in the guidelines [2,9,11]. There is no relevant literature regarding the use of MRI of the pelvis in the follow-up of patients on active surveillance, although data from 2 retrospective studies evaluating RCC staging with CT suggested that imaging of the pelvis had limited benefit for the detection of metastases [33,34]. Furthermore, metastatic progression occurs infrequently in patients on active surveillance with T1a renal masses [8,75-78,81,82]; therefore, MRI of the abdomen is preferred over MRI of the abdomen and pelvis.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRI Head Most patients with metastases to the central nervous system are symptomatic. Thus, active surveillance protocols for small localized renal masses have not supported routine imaging of the brain to search for metastases in asymptomatic patients. Brain imaging should be performed only in cases with suggestive signs or symptoms [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. MRU There is no relevant literature regarding the use of MRU in the surveillance of small localized renal masses, and this method is not recommended by the guidelines [2,9,11].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. US Kidney Retroperitoneal US of the kidney is an acceptable imaging modality for follow-up of small localized renal masses on active surveillance, especially once the growth rate of the renal mass has been established with CT or MRI [2,9,11,78]. US is an excellent method for characterizing cystic lesions and often provides supplementary information to the other imaging modalities. However, unenhanced US has an overall diagnostic accuracy for characterizing renal masses of only 30% [88]. Some concerns also exist regarding the reproducibility of measurements obtained with US and their correlation with measurements obtained with CT and MRI; any discrepancies could suggest a falsely positive or negative growth rate [82]. When US is used, some authors have recommended that any discrepancy in tumor size or growth rate or qualitative changes in tumor appearance should prompt imaging with CT or MRI [78].


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. Supporting Documents The evidence table, literature search, and appendix for this topic are available at https://acsearch.acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation.


Post Treatment Follow up and Active Surveillance of Renal Cell Carcinoma. For additional information on the Appropriateness Criteria methodology and other supporting documents, go to www.acr.org/ac.


Intensive Care Unit Patients

Intensive Care Unit Patients. In a prospective study of 253 LUS examinations performed for unexplained deterioration of arterial blood gases, the management was changed directly as a result of information provided by the LUS in 119 out of 253 cases (47%) [3]. In a study by Phillips and Manning [4], a total of 102 chest radiographs and pocket US examinations were performed in 66 patients in the coronary care unit. The pocket US demonstrated overall good concordance with chest radiographs ranging from 77% for pleural effusion to 92% for pneumonia. Additionally, the pocket US examination appeared to anticipate resolution of pulmonary edema prior to the chest radiographs. Compared with transthoracic echocardiography, pocket US had excellent sensitivity for cardiac findings with values ranging from 85% for left atrial enlargement to 100% for cardiomegaly but had limited specificity of cardiomegaly at just 51% [4].


Intensive Care Unit Patients

Intensive Care Unit Patients. A meta-analysis that included 10 full-text studies that included 543 patients in evaluating the diagnostic accuracy of chest radiographs, and when concomitantly studied LUS, in comparison with CT as the reference standard, for


Intensive Care Unit Patients

Intensive Care Unit Patients

Intensive Care Unit Patients. Intensive Care Unit Patients


Intensive Care Unit Patients

Intensive Care Unit Patients. OR Discussion of Procedures by Variant Variant 1: Admission or transfer to intensive care unit. Initial imaging. Radiography Chest Portable The strategy of ordering daily routine chest radiographs for critically ill and mechanically ventilated patients is slowly changing from daily chest radiographs to on-demand radiographs only. In a study evaluating the practice of chest radiographs in a Dutch ICU by Tolsma et al [6], 61% of the responding ICUs were said to never perform chest radiographs on a routine basis and that only 7% of responding ICUs were currently performing daily routine chest radiographs for all patients. In this study, they asked the intensivists to judge the clinical value (therapeutic efficacy) of routine and on-demand chest radiographs and to judge the value of an established radiologic evaluation with a radiologist and asked them to state some indications for routine chest radiographs. The therapeutic efficacy of routine chest radiographs was between 10% and 20% compared with that between 10% and 60% for on-demand chest radiographs.


Intensive Care Unit Patients

Intensive Care Unit Patients. In a prospective study by Mets et al [7] and a meta-analysis by Ganapathy et al [8], elimination of daily routine chest radiographs and a restrictive approach with chest radiographs performed to investigate clinical changes among critically ill patients led to a decrease in the total number of chest radiographs obtained per patient per day in the ICU, and, without negative influence on length of stay in the ICU and hospital, a decrease in the readmission rate.