For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), CT of the abdomen without IV contrast may be considered appropriate. 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]. 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. For patients in whom contrast is contraindicated (eg, previous anaphylactic reaction), CT of the abdomen without IV contrast may be considered appropriate. 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]. 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.