FDG-PET/MRI changed suspicion for bladder tumors in 36% of cases (50% increased, 50% decreased), for pelvic lymph nodes in 52% of cases (36% increased, 64% decreased), and for nonnodal pelvis in 9% of cases (100% increased). Another recent study using FDG-PET/MRI [43] demonstrated similar performance of FDG-PET/MRI (sensitivity 80%, specificity 56%) compared with CT (sensitivity 91%, specificity 43%) in detecting primary bladder tumors. However, evaluation of nodal status was limited, because of the lack of patients with true pathologic lymph nodes. Civelek et al [44] determined the clinical benefit of FDG-PET/MRI for surveillance and restaging of patients with locally advanced metastatic MIBC compared with conventional imaging methods. FDG-PET/MRI identified 82 metastatic malignant lesions involving lymph nodes, liver, lung, soft tissue, adrenal glands, prostate, and bone, with a resultant advantage of 36% for lesion visibility in comparison with CT. The researchers concluded that FDG-PET/MRI can detect metastatic lesions, which cannot be identified on conventional CT, and this can allow for better treatment planning and improve disease monitoring during therapy. Studies suggest that FDG-PET/MRI may not be necessary for staging NMIBC due to a low likelihood of nodal or metastatic disease [22,23]. MRI Abdomen and Pelvis Without and With IV Contrast Although there is no relevant literature to support the use of MRI abdomen and pelvis without and with IV contrast (separate from MRU) in the evaluation of NMIBC, it may be useful in some clinical situations. However, CTU and MRU are of greater usefulness because they allow for the comprehensive evaluation of the genitourinary tract, as well as the assessment of retroperitoneal and pelvic lymph nodes (see CTU and MRU sections).
Pretreatment Staging of Urothelial Cancer. FDG-PET/MRI changed suspicion for bladder tumors in 36% of cases (50% increased, 50% decreased), for pelvic lymph nodes in 52% of cases (36% increased, 64% decreased), and for nonnodal pelvis in 9% of cases (100% increased). Another recent study using FDG-PET/MRI [43] demonstrated similar performance of FDG-PET/MRI (sensitivity 80%, specificity 56%) compared with CT (sensitivity 91%, specificity 43%) in detecting primary bladder tumors. However, evaluation of nodal status was limited, because of the lack of patients with true pathologic lymph nodes. Civelek et al [44] determined the clinical benefit of FDG-PET/MRI for surveillance and restaging of patients with locally advanced metastatic MIBC compared with conventional imaging methods. FDG-PET/MRI identified 82 metastatic malignant lesions involving lymph nodes, liver, lung, soft tissue, adrenal glands, prostate, and bone, with a resultant advantage of 36% for lesion visibility in comparison with CT. The researchers concluded that FDG-PET/MRI can detect metastatic lesions, which cannot be identified on conventional CT, and this can allow for better treatment planning and improve disease monitoring during therapy. Studies suggest that FDG-PET/MRI may not be necessary for staging NMIBC due to a low likelihood of nodal or metastatic disease [22,23]. MRI Abdomen and Pelvis Without and With IV Contrast Although there is no relevant literature to support the use of MRI abdomen and pelvis without and with IV contrast (separate from MRU) in the evaluation of NMIBC, it may be useful in some clinical situations. However, CTU and MRU are of greater usefulness because they allow for the comprehensive evaluation of the genitourinary tract, as well as the assessment of retroperitoneal and pelvic lymph nodes (see CTU and MRU sections).