However, given the paucity of litereature for utility of fluoride PET/CT in the initial staging of RCC, current guidelines from the EAU and NCCN do not support routine fluoride PET/CT to search for metastases in asymptomatic patients in the initial staging of RCC [5,13]. MRI Abdomen and Pelvis MRI of the abdomen without and with IV contrast is considered a reliable method for the staging of RCC. Various MR sequences, including T2-weighted, chemical shift T1-weighted, contrast-enhanced T1-weighted, and diffusion- weighted images, are typically obtained for the staging of RCC. In a study involving 40 patients with RCC, MRI was reported to have an accuracy of 81% to 86% for T staging [62]. Breath-hold MRI showing a lack of perinephric fat involvement is reported to have a high negative predictive value for no perinephric tumor invasion [63]. In a study of 73 RCCs, Roy et al [64] showed that the presence of a pseudocapsule on MRI had an accuracy of 93% for clear-cell carcinomas in separating T1/T2 tumors from T3a tumors. Lal et al [65] performed a prospective observational study in 50 patients with RCC, comparing MRI with histopathological findings. In this study, MRI was reported to have a 90% agreement with histopathology for detecting perirenal extension and a 97% agreement with histopathology for detecting tumor extension beyond Gerota fascia [65]. Both contrast-enhanced multidetector CT and MRI are helpful in detecting venous involvement, particularly in the main renal vein and the IVC [33,66]. Increased diameter of the IVC and renal vein, presence of tumor signal both inside and outside the vessel wall, altered signal intensity in the vessel wall, presence of flow around the tumor thrombus, and mobility in different phases are some of the MRI features that are helpful in detecting venous involvement [67,68].
Staging of Renal Cell Carcinoma. However, given the paucity of litereature for utility of fluoride PET/CT in the initial staging of RCC, current guidelines from the EAU and NCCN do not support routine fluoride PET/CT to search for metastases in asymptomatic patients in the initial staging of RCC [5,13]. MRI Abdomen and Pelvis MRI of the abdomen without and with IV contrast is considered a reliable method for the staging of RCC. Various MR sequences, including T2-weighted, chemical shift T1-weighted, contrast-enhanced T1-weighted, and diffusion- weighted images, are typically obtained for the staging of RCC. In a study involving 40 patients with RCC, MRI was reported to have an accuracy of 81% to 86% for T staging [62]. Breath-hold MRI showing a lack of perinephric fat involvement is reported to have a high negative predictive value for no perinephric tumor invasion [63]. In a study of 73 RCCs, Roy et al [64] showed that the presence of a pseudocapsule on MRI had an accuracy of 93% for clear-cell carcinomas in separating T1/T2 tumors from T3a tumors. Lal et al [65] performed a prospective observational study in 50 patients with RCC, comparing MRI with histopathological findings. In this study, MRI was reported to have a 90% agreement with histopathology for detecting perirenal extension and a 97% agreement with histopathology for detecting tumor extension beyond Gerota fascia [65]. Both contrast-enhanced multidetector CT and MRI are helpful in detecting venous involvement, particularly in the main renal vein and the IVC [33,66]. Increased diameter of the IVC and renal vein, presence of tumor signal both inside and outside the vessel wall, altered signal intensity in the vessel wall, presence of flow around the tumor thrombus, and mobility in different phases are some of the MRI features that are helpful in detecting venous involvement [67,68].