Clinical presentation History \200 Distinguish true vomiting from regurgitation. \200 D uration of symptoms: acute, chronic, or recurrent. \200 Timing: relation to meals, early morning (pregnancy, raised intracranial pressure). Content of vomitus: bile, blood, coffee grounds, feces. \200 Abdominal pain, fever, diarr hea. \200 Constipation. \200 Headache, neck stiffness, focal neurology, vertigo. \200 Pregnancy symptoms, e.g. amenorrhea. \200 Weight loss. \200 Previous abdominal surgery : consider obstruction secondary to adhesions. Primary malignancy: obstruction or cerebral metastases. Clinical examination The most relevant \201 ndings to inform imaging are signs of obstruc tion (high pitched bowel sounds, peritonism or abdominal mass and signs of raised intracran ial pressure or focal neurology to indicate a CT head. Imaging The type of imaging will be guided by the differential diagnosis and the patient \200\231s age. Imaging is not indicated in many causes of vomiting, e.g. gastro- enteritis or pregnancy. The main role of imaging is to diagnose or exclude mechanical obstruction or intracranial pathology. Imaging may also play a role in diagnosing in \202 ammatory condit ions such as appendicitis. Plain \201 lm An abdominal radiograph is the \201 rst-line investigation in suspected b owel obstruction. Features include dilated bowel proximal to an obstruction with a paucity of gas distally. Look for free gas in associated perforation. SUBASH KC/NMC-15TH/2014 VOMITING 349 Ultrasound May be \201 rst-line investigation of neonates or infants with vomiting, e.g. ?pyloric stenosis or adults with features of in \202 ammatory causes, e.g. pancreatitis or cholecystitis. CT CT head is the investigation of choice in suspected neurogenic vomiting, e.g. post-head injury or in a patient with features of raised intracranial pressure or a known primary mal ignancy at risk of cerebral metastases. CT of the abdomen and pelvis is carried out in bowe l obstruction to look for the site and cause of obstruction. Other in \202 ammatory causes of vomiting such as appendicitis, pancreatitis, and cholecystitis may be detected. Fluoroscopy Upper GI contrast studies are used in suspected gastric outlet obstruction and in children. Nuclear medicine Radionuclide gastric emptying study may be used in investigation of unex- plained nausea and vomiting. SUBASH KC/NMC-15TH/2014 350 CHAPTER 22 Gastrointestinal presenting syndromes Jaundice Jaundice is clinically detectable when the serum bilirubin concentration is in exc ess of 50 mol/L (with a normal value of <1750 be due to \200\230pre-hepatic \200\231 ca uses (haemolysis of red blood cells), \200\230hepatic \200\231 causes (including congenita l syndromes, hepatitis, and cirrhosis), and \200\230post-hepatic \200\231 or obstructive c auses (obstruction of bile secretion distal to the bile canaliculi by stones, strictures, o r carcinoma). Imaging is most useful in this latter group. mol/L). It can Clinical presentation Patients may present as they notice yellow discoloration of the skin and eyes, with severe itching or with weight loss, dark urine, and steatorrhoea. Abdominal pain may be a feature, mostly in association with the more benign causes of jaundice, altho ugh not always. Alternatively, deranged liver function tests may be detected during investi gation of other condi- tions or during routine follow-up or preoperative investigation. Imaging Plain \201 lms Gallstones may be visualized in the right upper quadrant. Only 10 gallstones calcify and are radio-opaque so their absence does not exclude gallbladder patho logy. Also, gallstones are a common \201 nding within the population, such that their pre sence is not necessarily causative. Remember, there could be other \201 ndings on the pla in \201 lms which may point to the cause of jaundice such as metastatic deposits, lung ma ss, etc. % of Ultrasound The main investigation in jaundiced patients. This allows assessment of liver ar chitecture in cirrhosis, the presence of focal lesions and assessment of the biliary tree ( gallstones or bile duct obstruction with duct dilata- tion). In the case of duct dilatation , ultrasound may suggest a mass in the head of pancreas or duodenum, or \201 lling defect s within the biliary system, which will need further imaging with CT or MR cholangiopancrea tog- raphy (MRCP) depending on the clinical picture. Ultrasound is also used for imaged-gui ded liver biopsy, and may also detect additional pathology such as ascites, splenomegaly, a nd allow assessment of the portal vein in chronic liver disease. In infants, choledochal cy sts may cause obstructive jaundice or ultrasound may demonstrate a small/absent gallbladder and triangular cord sign in biliary atresia. CT Used when obstructive jaundice is present and the likely cause is a malignant process. A staging chest abdomen and pelvis CT should be performed. Nuclear medicine In infants with jaundice, a HIDA (hydroxy iminodiacetic acid) scan is used to demonstrate whether any biliary excretion of isotope occurs (it doesn \200\231t in the case of biliary atresia). SUBASH KC/NMC-15TH/2014 JAUNDICE 351 MRI MRCP should be performed when ultrasound has shown obstructive jaundice and further del ineation of the point of obstruction is needed. Most useful for stone disease, although eno ugh detail is usually present to comment on the pancreas in malignancy. This investigation allows ERCP to be reserved solely for patients who require intervention. Fluoroscopy ERCP can be used to perform spincterotomy and stone removal in the case of obst ructive jaundice following appropriate imaging. Fluoroscopic transjugular liver biopsy may be necessary if the patient \200\231s clotting cannot be corrected enough to allow safe per cutaneous biopsy. Information for the radiologist \200 Is the jaundice painful or painless? If painless and the gallbladder is palpable then malignant process is more likely than stone disease (Courvosier \200\231s law ). Do the liver function tests indicate an obstructive or hepatitic picture? \200 Are there any other features in the history to suggest stone disease versus malignant process? Are there any clues on the plain \201 lms to guide further investigation? SUBASH KC/NMC-15TH/2014 352 CHAPTER 22 Gastrointestinal presenting syndromes Melaena Melaena is the black tarry feces that are passed following GI haemor- rhage. The bl ack color occurs as the iron in hemoglobin oxidizes as it passes through the GI tract. Most ly, melaena occurs around 14 hours after bleeding has occurred as it takes around this time for oxidization of the iron to occur, and is usually due to upper GI bleeding such as from the stomach, duodenum, or small bowel (proximal to the ligament of Trietz). Clinical presentation Patients may present with symptoms and signs of anemia and have a pos i- tive fecal occult blood test. Following large bleeds, patients may present with signs of shock. The differential diagnosis of melaena is wide, encom- passing ulcer disease, varice al bleeding, neoplasm, and vascular lesions. Over the last few years the role of imaging ha s changed from being purely diagnostic to identifying the site of bleeding and underlying p athology, to playing a key role in treatment of the bleed itself. Imaging Endoscopy remains the \201 rst-line investigation for patients with acute upper G I bleeds. CT However, following a negative endoscopic study, in the presence of active bleeding, a CT A would be appropriate. Essential diagnostic tool: a rapid, non-invasive, sensitive investigation which allows precise localization of bleeding point with concurrent identi \201 cation of underlying cause and allows accurate intervention planning. Requires a bleeding rate of aro und 0.3ml/min. Imaging will show extravasation of high attenuation contrast material into t he bowel lumen. Nuclear medicine Technetium-labeled red blood cell or sulfur colloid scans can be per- form ed to identify and localize chronic GI bleeding. It is a sensitive test in situations of in termittent bleeding or ongoing low volume blood loss (as low as 0.04ml/min), however, in th e acute situation of an active, large GI bleed then endoscopy or CT angiograms are clinical ly more appropriate. Angiography Mostly used for therapeutic embolization of bleeding vessels, although can be d iagnostic should other modalities fail to identify any bleeding sites, or the patient is ac utely unstable. Bleeding rates as low as 0.5ml/min can be detected. The majority of upper G I bleeds will involve vessels arising from the coeliac axis or superior mesenteric artery. The rich collateral supply from these branches allows safe embolization of a bleeding vesse l branch with low risk of ischaemic injury. Information for the radiologist \200 Has the patient had a recent CT or barium study? Ret ained contrast within the bowel can lead to false positives in CTA. How haemodynamically stable is the patient? SUBASH KC/NMC-15TH/2014 IRON DEFICIENCY anemia 353 Iron de \201 ciency anemia Iron de \201 ciency anemia in the setting of GI disorders is c aused by chronic low volume blood loss. Causes \200 GI malignancy. \200 In \202 ammatory: Crohn \200\231s and UC. \200 Malab sorption syndromes: coeliac disease, Whipple \200\231s disease. \200 Hematological condit ions such as leukemia and lymphoma. \200 Infective: parasitic infections. Imaging Plain \201 lm Usually the \201 rst modality used to assess the abdomen to ident ify bowel dilatation or hepatosplenomegaly. Barium examinations \200 These are often performed in the setting of iron de \201 ciency anemia to assess the GI tract for malignancy, signs of in \202 ammatory bowel disease, or malabsorpt ion. Upper GI examinations look at the esophagus and the stomach. \200 Areas of stricturing, b owel wall thickening, mucosal ulceration, and \201 stulation can be identi \201 ed with accuracy. CT \200 CT is another common modality to assess the abdomen for iron de \201 ciency anemia. CT has a high sensitivity and speci \201 city for identifying the site of bowel abnormality, any perforation or collections, and is used to stage bowel malignancy. CT colonoscopy is a method of imaging the large bowel in a way similar to colonoscopy. Origin of masses can be accurately identi \201 ed and staged. Information for the radiologist \200 Clinical presentation and previous chronic diseases such as Crohn \200\231s disease or surgical history. Clinical \201 ndings. \200 Hematological \201 ndings, in \202 ammatory markers, tumo r markers, and renal function. Colonoscopy \201 ndings if any. SUBASH KC/NMC-15TH/2014 354 CHAPTER 22 Gastrointestinal presenting syndromes Diarrhea Diarrhea has many causes. The majority of cases of diarrhea are infec- tive and do not need imaging. Causes \200 Infective, e.g. Clostridium dif \201 cile . \200 In \202 ammatory: Crohn \200\231s disease and UC. \200 Ischaemic colitis. \200 Malignancy: carcinoid, colonic c arcinoma. Imaging Plain \201 lm Often the \201 rst modality used to assess the abdomen and will i dentify bowel dilatation or a large soft tissue mass. Small bowel is identi \201 ed by the presence of the valvulae conniventes, the folds that traverse the lumen. Large bowel shows interdigitating haustral folds. A search for free air needs to be performed. Finally, if t here is concern about in \202 ammatory bowel disease, colonic dilatation, particularly tra nsverse colon, needs to be measured. Thickening of the bowel wall gives an appearance known as \200\230thumb-printing \200\231. Small bowel follow through and barium enemas \200 May be performed in the setting of chro nic diarrhea to look for small bowel or colonic pathology. Areas of stricturing in the small or large bowel, wall thickening, mucosal ulceration, and \201 stulation can be identi \201 ed with accuracy. CT \200 CT is another common modality to assess the abdomen in the setting of diarrhea. CT has a high sensitivity and speci \201 city for identifying the site of bowel abnormality, any perforation or collections, and is used to stage bowel malignancy. MRI MR enterography is increasingly being used to monitor in \202 ammatory bowel disease t o identify abnormal bowel, assess disease activity, and identify complications. Information for the radiologist \200 Clinical presentation and previous chronic diseases such as Crohn \200\231s disease or surgical history. Clinical \201 ndings. \200 In \202 ammatory markers and renal function. \200 Colonos copy \201 ndings if any. SUBASH KC/NMC-15TH/2014 ABDOMINAL DISTENSION 355 Abdominal distension Abdominal distension may be caused by masses, ascites, or bowel obstru ction. Clinical presentation \200 Non-speci \201 c abdominal pain. \200 Malaise and weight lo ss. \200 Abdominal distension: Soft with signs of obstruction? \200 Mass on palpation. \200 Shifting dullness suggesti ve of ascites. Imaging Plain \201 lm Often the \201 rst modality used to assess the abdomen. It will i dentify bowel dilatation or a large soft tissue mass. If the plain \201 lm shows bowel di latation and clinically the patient is obstructed, CT is the next imaging modality. If ther e is a suspicion of a mass, either an ultrasound or a CT can be performed. Ultrasound \200 An abdominal ultrasound is performed after fasting for 6 hours, with a full bladder. Ultrasound is useful to look at the solid abdominal organs, especially the liver and spleen. The aorta can also be assessed for aneurysms. It can also identify any free \202 uid or ascites. \200 Mesenteric and para-aortic lymp hadenopathy can often be visualized. \200 A TA pelvic scan may show the uterus and ovarie s if the bladder is full, alternatively a TV scan may be performed. CT CT has a high sensitivity and speci \201 city for identifying the site of bowel obstruc tion. Masses can be accurately identi \201 ed and staged. MRI MRI is mainly used in assessment of gynecological masses. Information for the radiologist Salient features from the clinical history and examination to point towards a diagnosis. SUBASH KC/NMC-15TH/2014 356 CHAPTER 22 Gastrointestinal presenting syndromes Weight loss Weight loss that is unintentional is medically signi \201 cant. Although a ver y non-speci \201 c symptom, there may be serious underlying pathology. There are a multitu de of causative factors ranging from inadequate food intake (loss of appetite, vomiting, dy sphagia), to malabsorption (in \202 ammatory bowel disease, chronic pancreatitis, \201 s tulae) and increased metabolism (tumors, chronic infection, endocrine abnormalities). Clinical presentation Patients may present having noticed a change in their body habitus or noticed that their clothes are loose. Alternatively, others may have commented on a change in appearance. They may have accompanying symptoms of fatigue, lethargy, GI changes, or fe atures of the underlying disease. Imaging Plain \201 lm A CXR is a good initial investigation of weight loss, and may demon strate primary tumor, metastatic bone disease, cardiac failure, or chronic infec- tion such as TB. Ultrasound Diagnostic yield is lower with ultrasound than CT but will show metastatic depos its in the liver if present. CT Used to search for occult malignancy, although the sensitivity is often low. Should iden tify malignant causes such as lymphoma, lung, and GI tumors. May suggest in \202 ammatory bowel disease if the bowel wall is thickened. Chronic chest infection can also be clari \201 ed with CT. Fluoroscopy A barium swallow can be used to diagnose swallowing problems and upper GI contr ast studies are useful in the case of achalasia and oesopha- geal disease. Information for the radiologist Are there any speci \201 c symptoms present which may guid e investigation? SUBASH KC/NMC-15TH/2014 357 Chapter 23 Gastrointestinal conditions Oesophageal cancer Gastric cancer 360 Colonic cancer 362 Rectal cancer 364 Gastrointestinal lymphoma Liver tumors 368 Cholangiocarcinoma 370 Pancreatic cancer 372 Achalasia, hiatus h ernia, and re \202 ux Appendicitis 376 Cholecystitis/cholangitis 378 Stomach/duodenal ulce ration Crohn \200\231s disease 382 Ulcerative colitis 384 Infective colitis 386 Small bowel obstruction 388 Large bowel obstruction 390 Paralytic ileus and pseudo-obstruction Gastroi ntestinal perforation 394 Subphrenic abscess 396 Diverticular disease 398 Volvulus 400 Intu ssusception Acute pancreatitis 404 Chronic pancreatitis 406 Cirrhosis 408 Ascites 410 Herni a 412 358 366 374 380 392 402 SUBASH KC/NMC-15TH/2014 358 CHAPTER 23 Gastrointestinal conditions Oesophageal cancer \200 Incidence: 9 th commonest cancer (UK). Risk factors: male:female 5:1, diet, excess alcohol, smoking, ac halasia, Plummer \200\223Vinson syndrome, obesity, re \202 ux Barrett \200\231s esophag us. 5-year survival poor but improved, around 8 % . Site: 20 \200 Pathology: squamous (upper/mid) or adenocarcinoma (lower, % upper, 50 % middle, 30 % lower esophagus. incidence rising). Clinical presentation Progressive dysphagia, weight loss, chest pain. TNM staging \200 Tis: carcinoma in situ . \200 T1: invading lamina propria/submucosa. \200 T2: invading muscularis propria. \200 T3: invading adventitia. \200 T4: invasion of adjacent structures. \200 Nx: nodes cannot be assessed. \200 N0: no node spread. \200 N1: regional node metastasis. \200 M0: no distant spread. \200 M1: distant metast asis. Imaging OGD is the investigation of choice, allowing direct visualization, assess- ment of severity of stenosis and biopsy. Therapeutic in the removal of small tumors/stenting. Plain \201 lm Generally not helpful, may see widened mediastinum/dilated esophagus, compl ications such as aspiration pneumonia, pulmonary metastases. CT (Fig. CT used for tumor staging, to de \201 ne the local extent of the tumor, detecting mediastinal invasion, lymphadenopathy, and distant metastases. 23.1 ) Fluoroscopy Contrast swallow appearances include a mass or an in \201 ltrating lesion caus ing stenosis, occasionally ulceration and mucosal irregularity. EUS EUS is the investigation of choice for local staging. The layers of the oesophageal wal l and perioesophageal tissues are visible and therefore depth of tumor invasion and local n odal disease can be determined. Problems arise, however, if a signi \201 cant oesophageal stenosis exists. PET Superior to CT in the detection of loco-regional/distant lymphadenopathy and metastases . Now an important part of preoperative imaging. Information for the radiologist Clinical history and duration of symptoms with emphasis of features sug- gestive of malignancy are essential. Endoscopic level and biopsy results. SUBASH KC/NMC-15TH/2014 OESOPHAGEAL CANCER 359 (a) (b) Fig. 23.1 esophagus (arrowed) in a patient with oesophageal cancer. Note also low attenua- tion metastasis within the upper liver. b) Coronal image from PET-CT scan, showing intense uptake of an oesophageal tumor (cross). Other areas of increased uptake correspond to physi ological uptake. a) Coronal CT showing circumferential thickening of the lower SUBASH KC/NMC-15TH/2014 360 CHAPTER 23 Gastrointestinal conditions Gastric cancer \200 Incidence: UK 23/100,000/year. Incidence increased at gastro-oesophag eal junction, decreased distal and body gastric cancers. Male:female 2 \200\2233:1. Adenocarcinoma accounts for > 95 % malignant tumors stomach, other tumors include lymphoma and GIST. Risk factors: Helicobacter pylori , atrophic gastritis, smoking, pernicious anemia, blood group A, adenomatous polyps, diet. 5-year survival rates remain low at about 15 % . Clinical presentation Often non-speci \201 c and late. New-onset dyspepsia, dysphagia, vom iting, anorexia, weight loss, or haematemesis warrant investigation. Patients with advanced disease often have constitutional symptoms of anorexia and weight loss. TNM staging \200 Tis: carcinoma in situ . \200 T1: invading lamina propria/submucosa. \200 T2: invading muscularis propria/subserosa. \200 T3: penetrates subserosa. \200 T4 : invasion of adjacent structures. \200 N1: metastasis to 1 \200\2236 regional nodes. \200 N2: metastasis to 7 \200\22315 regional nodes. \200 N3: metastasis to > 15 regional nodes. \200 M0: no distant spread. \200 M1: distant metastasis. Imaging OGD (and biopsy) is the investigation of choice for diagnosing gastric cancer. The role of imaging is in the accurate preoperative staging of the disease once a diagnosis has been established. Laparoscopy performed in patients considered for radical surgery, as may identify occult peritoneal metastasis. CT (Fig. CT provides staging information on the tumor mass, loco-regional/ distant lymphade nopathy, and metastatic spread of disease. 23.2 ) EUS In patients with no evidence of distant disease, EUS may be used to eval- uate local ex tent of the tumor as it able to de \201 ne the individual layers of the gastric wall and t hus accurately assess the depth of invasion of the gastric tumor and local invasion. PET Role is still being evaluated; may have a role in recurrent disease and assessment of t reatment response. SUBASH KC/NMC-15TH/2014 GASTRIC CANCER 361 Information for the radiologist Clinical history and duration of symptoms with emphasis on features con- sistent with malignancy are essential. Endoscopic evaluation and histolog- ic al diagnosis is important before embarking upon staging investigations if the patient is a candidate for active treatment. Fig. 23.2 lymphadenopathy (short arrows), and extension into the perigastric fat (long arro w). Low attenuation lesions within the liver are metastases. Axial CT showing abnormal thickening of the stomach, with local SUBASH KC/NMC-15TH/2014 362 CHAPTER 23 Gastrointestinal conditions Colonic cancer \200 UK: 3 rd commonest malignancy; 2 nd commonest cancer death. Risk factors: chronic in \202 ammatory bowel disease, hereditary polyposis and non-polyposis sy ndromes, previous bowel cancer, smoking. Majority adenocarcinomas arise in pre-existing adenomatous polyps. Clinical presentation \200 Most tumors arise in the left colon, causing rectal bleeding, altered bowel habit, and colicky pain. Right-sided tumors present with iron de \201 ciency anemia/RIF mass. TNM staging \200 Tis: carcinoma in situ . \200 T1: invading submucosa. \200 T2: invad ing muscularis propria. \200 T3: invading through muscularis propria. \200 T4: invasion of adjacent structures/perforates peritoneum. \200 N0: no node spread. \200 N1: metast asis in 1 \200\2233 regional nodes. \200 N2: metastasis in \211 4 regional lymph nodes. \200 M0: no distant spread. \200 M1: distant metastasis. Imaging Colonoscopy is the \201 rst-line test for tumor detection and biopsy. Imaging stu dies are less invasive, indicated in patients unable to undergo/ failed colonoscopy. CT col onography (CTC) has overtaken double con- trast barium enema (DCBE) as the colorectal imagi ng method of choice, with better sensitivity, and speci \201 city approaching colonoscopy. Plain \201 lm Useful in suspected acute bowel obstruction (presenting feature in <20 of t umors), perforation, and detection of pulmonary metastases. % CT (Fig. CTC requires bowel preparation and gaseous distension to allow visibility of intra luminal lesions. It may show extramural in \201 ltration or synchronous lesions. Extra-col onic structures can also be evaluated. Staging is by CT chest, abdomen, and pelvis to asses s local stage and metastases. 23.3 ) Fluoroscopy DCBE may demonstrate a malignant polyp as an intraluminal \201 lling defect, advanced tumors have annular appearance ( \200\230apple-core \200\231 deformity). If acutel y obstructed, stenting may have a role. Nuclear medicine Combined PET/CT is a useful adjunct in detection of recurrent cancer. Isot ope bone scan can be performed for suspected bone metastases. SUBASH KC/NMC-15TH/2014 COLONIC CANCER 363 Information for the radiologist \200 If there are symptoms of acute obstruction. \200 I f known tumor, exact location, or suspicion from clinical signs, e.g. anemia. CEA. \200 Relevant risk factors. Fig. 23.3 descending colonic tumor. Endoluminal view from the CT colonoscopy showing tumor. Coronal CT showing large bowel obstruction secondary to proximal SUBASH KC/NMC-15TH/2014 364 CHAPTER 23 Gastrointestinal conditions Rectal cancer \200 Approximately 20 are adenocarcinomas. % of colorectal cancers occur in the rectum; majority Although risk factors are similar to colonic tumors, investigation and treatment are different. Clinical presentation Change in bowel habit (diarrhea or constipation), tenesmus, bleeding, non-speci \201 c symptoms, e.g. tiredness, weight loss. Imaging Plain \201 lm Useful in suspected acute bowel obstruction, perforation, and detec tion of pulmonary metastases. Ultrasound Transrectal ultrasound is better at depicting the layers of the rectal wall than MRI, useful in the assessment of early wall involvement and selecting T1 N0 tumors for loc al excision. CT May be useful if the rectal lesion cannot be traversed with the colono- scope, to evalua te the rest of the bowel, as synchronous carcinomas are seen in 5 % of cases, and synchrono us adenomas in 27 \200\22355 colonic structures can also be evaluated. Staging is by CT che st, abdomen, and pelvis to assess local stage and metastases. % cases. Extra- MRI (Fig. Indicated for staging rectal tumors, performed to assess involvement of mesorecta l fascia and suitability for total mesorectal excision. Nodal/venous involvement is also as sessed and the need for neoadjuvant treatment. 23.4 ) Fluoroscopy DCBE may demonstrate a malignant polyp as an intraluminal \201 lling defect, advanced tumors have annular appearance ( \200\230apple-core \200\231 deformity). If acutel y obstructed, stenting may have a role for more proximal rectal tumors. Nuclear medicine Combined PET/CT is a useful adjunct in detection of recurrent rectal cance r. Information for the radiologist \200 Level of tumor from the anal verge. \200 Any contr aindication to MRI. \200 CEA level. SUBASH KC/NMC-15TH/2014 RECTAL CANCER 365 (a) (b) Fig. 23.4 posterior wall of the lower rectum (arrow). b) Sagittal MRI showing locally advan ced tumor of the rectum, extending anteriorly into the bladder and posteriorly to the sacru m. a) Sagittal MRI scan of a patient with an early villous tumor of the SUBASH KC/NMC-15TH/2014 366 CHAPTER 23 Gastrointestinal conditions Gastrointestinal lymphoma \200 Site: stomach > small bowel > colon \200 Usually diffuse large B-cell ( 50 \200 Risk factors: coeliac disease, immunoproliferative small-intestin al disease (alpha-chain disease), chronic lymphatic lymphoma, previous extra-intestinal lym phoma. > pancreas > esophagus. % )/marginal zone/MALT ( 40 % ). Clinical presentation \200 General malaise and anorexia. \200 Symptoms of intestinal ob struction if the affected bowel lumen is compromised. May give rise to intussusception. \200 Dysphagia if the esophagus is affected. Imaging For diagnosis, monitoring of response or complications of therapy. Plain \201 lm Chest radiograph may demonstrate lymphadenopathy. Fluoroscopy Barium swallow/meal/enema may show large irregular mural \201 lling defects/ \201 ne submucosal nodules/thickening of folds. Ultrasound \200 Can assess spleen/liver, but dif \201 cult to assess in \201 ltrative d isease. \200 Good for assessment of super \201 cial nodal masses, and ultrasound- guided biopsies can be performed to gain tissue diagnosis. CT (Fig. Most useful investigation. The extent of spread of the mass and evaluation of site s of neoplastic involvement can be demonstrated. 23.5 ) PET May be used to identify active disease prior to, or post treatment. Information for the radiologist \200 Clinical symptoms if primary presentation \200\224 therefore choice of most appropriate radiological investigation can be made. Biopsy results. \200 Relevant past medical history, e.g. coeliac disease. SUBASH KC/NMC-15TH/2014 GASTROINTESTINAL LYMPHOMA 367 Fig. 23.5 with lymphoma. The bowel is thickened, with a dilated lumen, and there is no prox imal obstruction. Axial CT showing circumferential thickening of the caecum, in a patient SUBASH KC/NMC-15TH/2014 368 CHAPTER 23 Gastrointestinal conditions Liver tumors \200 Benign: haemangiomas are the commonest liver lesions, along with hepatic adenomas and focal nodular hyperplasia. Malignant: hepatocellular cancer (HCC) is one of the world \200\231s commonest cancers. It is associated with chronic liver disease, particularly hepatitis B and C. Metastases can occur in the liver commonly from colon, lung, breast, pan- creas and stomach cancers. Clinical presentation \200 Pain (as the liver capsule is stretched). \200 Deranged LFTs or jaundice. \200 Anorexia or weight loss. \200 Many liver tumors are small and clinic ally undetected. In metastatic disease, symptoms may only be apparent from the primary tumor. Imaging Ultrasound Good \201 rst-line test, used for follow-up of patients at risk of HCC . Used for image guided-biopsy. CT (Fig. \200 Follow-up of patients with a known primary malignancy that is known 23.6 ) to have spread to the liver. Different timing of contrast enhancement may be used depending on the type of tumor. MRI Excellent tool for problem-solving of liver tumors if a lesion identi \201 ed on ultra sound or CT requires further characterization. Information for the radiologist \200 Relevant medical history, e.g. malignancy, cirrhosis , long-term use of the oral contraceptive pill (adenoma risk factor). Hematology and biochemistry results: especially LFTs, and clotting if a biopsy is to be performed. SUBASH KC/NMC-15TH/2014 LIVER tumors 369 Fig. 23.6 keeping with metastases. Axial CT showing multiple low attenuation lesions within the liver, in SUBASH KC/NMC-15TH/2014 370 CHAPTER 23 Gastrointestinal conditions Cholangiocarcinoma \200 > 95 % adenocarcinoma, arise from biliary epithelium. \200 Risk factors: age ( > 60 years), chronic in \202 ammation, e.g. primary sclerosing cholangitis , viral hepatitis, cirrhosis and liver \202 uke (parasitic) infestation only account for a few. Classi \201 ed as intrahepatic, hilar (Klatskin) or extrahepatic (most common). Clinical presentation \200 Often progress insidiously and present late. \200 Poor progn osis: 5-year survival rate <5 % . \200 Extrahepatic present with painless obstructive jau ndice. \200 Intrahepatic tumors present with non-speci \201 c symptoms such as anorexia, weight loss, abdominal pain. Cholangitis is an unusual presentation. TNM staging \200 TIS: carcinoma in situ . \200 T1a: invades mucosa. \200 T1b: invades muscularis. \200 T2: invades perimuscular connective tissue. \200 T3: invades adjacent structures. \200 N0: no node spread. \200 N1: metastasis in cystic duct/peridochal/hil ar nodes. \200 N2: metastasis in peripancreatic, periduodenal, periportal, coeliac, or superior mesenteric nodes. \200 M0: no distant spread. \200 M1: distant metastasis (inc luding lymph node metastases beyond N2). Imaging Ultrasound (Fig. First-line investigation for obstructive jaundice. The tumor is ra rely seen, its location correlates with point of biliary tree caliber change. Detection of metastases, biliary duct dilatation, and exclusion of gallstones. 23.7a ) CT (Fig. Used in staging of cholangiocarcinomas, to identify the cause of biliary obstructi on, lymph nodes, and metastases. 23.7b ) MRI Superior to CT in identifying intraductal lesions and their extent owing to its greater soft tissue contrast resolution. ERCP \200 ERCP may establish the diagnosis by obtain brushings, and intraductal biopsies. Therapeutic procedures, such as stent insertion to relieve biliary obstruction ma y be performed. EUS is sensitive for assessing loco-regional lymphadenopathy and biopsy. PET PET remains an emerging technique for staging cholangiocarcinoma. SUBASH KC/NMC-15TH/2014 CHOLANGIOCARCINOMA 371 Information for the radiologist Duration of symptoms with emphasis on features suggestive o f malignancy. Severity of obstructive jaundice is useful (degree of derangement LFTs). Sign s suggestive of cholangitis (raised WCC, CRP) should prompt urgent discussion with a view t o ERCP. (a) (b) Fig. 23.7 showing dilated intrahepatic ducts, secondary to a \201 lling defect within the duct, washings at ERCP con \201 rmed cholangiocarcinoma. a) Ultrasound image showing dilated intrahepatic ducts. b) Axial CT SUBASH KC/NMC-15TH/2014 372 CHAPTER 23 Gastrointestinal conditions Pancreatic cancer \200 Incidence: 11 \200 Risk factors include smoking, age, chronic pa ncreatitis, diabetes th commonest cancer in UK and rising. mellitus, obesity. 90 % are adenocarcinomas arising from pancreatic duct epithelium. 5-year survival <2 % . Clinical presentation Often present with advanced disease. 80 % of pancreatic tumors arise in the pancreatic head; classically present with painless obstructive jaundice (Courvoisier \200\231s law \200\224 if palpable gallbladder jaundice is unlikely due to gall- stones). Constitutional symptoms are common. Late onset diabetes and pancreatitis are recognized bu t infrequent presentations. TNM staging \200 T1: tumor limited to pancreas \211 2cm. \200 T2: tumor limited to pa ncreas > 2cm. \200 T3: tumor extends beyond the pancreas without involvement of the coeliac axis or superior mesenteric artery. T4: tumor involvement of the coeliac axis or superior mesenteric artery. N0: no regional lymph node metastasis. \200 N1: regional lymph node metastasis. \200 M0 : no distant spread. \200 M1: distant metastasis. Imaging Ultrasound Primary investigation in obstructive jaundice. The liver, biliary tree, and gallbladder are assessed for metastases, biliary duct dilatation, and for the exclusion of gallstones respectively. Views of the pancreas often limited. CT (Fig. Triple-phase CT of the pancreas is the modality of choice for detecting and stagin g pancreatic cancer. Useful in assessment of resectability (local invasion of major vascula r structures). Accurately identi \201 es loco-regional/ distant lymphadenopathy and metast atic disease. 23.8 ) MRI MRI similar performance as CT, better at characterization of small lesions and assessin g resectability. EUS Bene \201 t of enabling biopsy along with tumor staging. ERCP For stent insertion, brushings and cytology. PET Useful for lesion detection when CT not identi \201 ed mass, and detection of occult m etastases. SUBASH KC/NMC-15TH/2014 PANCREATIC CANCER 373 Information for the radiologist Clinical history and duration of symptoms are important wit h emphasis on features suggestive of malignancy. An indicator of the severity of obstruc- t ive jaundice is useful. Symptoms/signs and biochemical parameters (raised WCC, CRP) suggest ive of cholangitis should prompt urgent discussion with a view to ERCP. Fig. 23.8 \200\230double duct \200\231 dilatation, i.e. dilatation of the intra- and extra hepatic biliary tree, and pancreatic duct, secondary to a large low attenuation mass within the pancreas (arrowed). Coronal CT image from a patient with pancreatic cancer. The CT shows SUBASH KC/NMC-15TH/2014 374 CHAPTER 23 Gastrointestinal conditions Achalasia, hiatus hernia, and re \202 ux \200 Achalasia: oesophageal motility disorder w ith failure of relaxation of the lower oesophageal sphincter and disordered peristalsis. Hiatus hernia: protrusion of stomach into the thoracic cavity. Two types; sliding (commonest) and rolling. Gastro-oesophageal re \202 ux disease (GORD): range of symptoms caused by re \202 ux of g astric acid into the lower esophagus. Often secondary to lower oesophageal sphincter incomp etence. Clinical presentation Dif \201 cult to discriminate reliably between these diagnoses owing to cross- over in symptomatology. Heartburn, acid re \202 ux often worse after meals and on lying \202 at, dysphagia and chest pain are common. Dysphagia to solids/liquids with r egurgitation of food is suggestive of achalasia. Imaging Several imaging techniques available to aid diagnosis including endoscopy, barium s tudies, and radionuclide techniques. Oesophageal manometry and pH measurements are physiolo gical investigations, the latter of which is the gold standard for diagnosing oesophageal m otility disorders but is limited by invasiveness, time-consumption, and lack of availabilit y. Plain \201 lm Often incidental \201 nding. Retrocardiac soft tissue density suggestive of a hiatus hernia. Dilated esophagus may be seen in achalasia. air- \202 uid levels are Fluoroscopy (Fig. Double-contrast barium swallow is sensitive for investigation of oesopha- geal disorders and superior to endoscopy in identifying motility disorders. Accurate at id entifying achalasia ( \200\230bird \200\231s beak \200\231 appearance), classifying hernias and visualization of re \202 ux of barium. 23.9 ) Nuclear medicine Rarely used in assessment of motility disorders and GORD. Ingestion of 99m Tc radiolabelled foods/liquids. Information for the radiologist Features suggestive of malignancy, such as progressive dysp hagia, anorexia, weight loss, and anemia is essential. SUBASH KC/NMC-15TH/2014 ACHALASIA, HIATUS HERNIA, AND REFLUX 375 Fig. 23.9 tapering to a \200\230bird \200\231s beak \200\231 narrowing at the gastro-oesop hageal junction. Double-contrast swallow shows abnormal dilatation of the esophagus, SUBASH KC/NMC-15TH/2014 376 CHAPTER 23 Gastrointestinal conditions Appendicitis \200 Common cause of acute abdominal pain. \200 May require emergency surg ery to prevent complications of perforation and peritonitis. Clinical presentation \200 Highest incidence age 10 \200\22319 years. \200 Classical pr esentation (<50 % ) central abdominal pain migrating to right iliac fossa, accompanied by fever, anorexia, nausea, and vomiting. Presentation in the very young and the elderly may be less typical with a rapidly progressing course. Clinical signs: rebound tenderness, right iliac fossa tenderness (McBurney \200\231s point), Rovsing \200\231s sign (right iliac fossa pain on palpation of left iliac fossa). Imaging Plain \201 lm \200 Appendicolith seen in <10 % of cases. \200 Non-speci \201 c features include lumbar scoliosis concave to the right, loss of the right pro-peritoneal fat stripe or psoas shadow, and distal small bowel obstruction. Ultrasound \200 High-frequency linear probe using graded compression. \200 Highly opera tor dependant, most useful in the young/thin. \200 Classic \201 ndings are of a blind e nding, non-compressible tubular structure with diameter > 6mm and hyperaemia. Additional \201 ndings may include localized \202 uid collection or abscess and an appendicolith. Retro-caecal appendix may be dif \201 cult to identify. CT (Fig. Considered by many to be the gold standard investigation but used with caution in children and women of childbearing age due to radiation risks. CT features include a disten ded, enhancing appendix measuring diameter, lack of oral contrast in the appendiceal lumen and stranding of the peri-appendiceal fat. 23.10 ) > 6mm in Information for the radiologist \200 Clinical features of pyrexia and raised in \202 amm atory markers. \200 In females: last menstrual period and any gynecological symptoms. SUBASH KC/NMC-15TH/2014