A recent retrospective analysis by Chen et al [40] of 168 patients with pathologically confirmed NMIBC who underwent preoperative CTU were divided into low-, medium-, high-, and very-high-risk groups based on the European Society of Urology guidelines [22] and then further analyzed based on tumor size, location, number, and various tumor characteristics including size of base and perivesical stranding at diagnosis [40]. These data were then used to attempt to stratify patients at higher risk for recurrences, which is important because these recurrences can become MIBC and metastasize [41]. This was a preliminary study that demonstrated the feasibility of using preoperative CTU features to predict the risk stratification of NMIBC, but further validation in a larger population is needed. Combinations of CT features and other characteristics may further improve the performance of the model and provide more accurate information for patient evaluation. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is not ideal for evaluating the urinary collecting system because FDG is excreted through urine, but it can be useful in detecting distant metastases. Studies suggest that FDG-PET/CT may not be necessary for staging NMIBC because of a low likelihood of nodal or metastatic disease [22,23]. FDG-PET/MRI Skull Base to Mid-Thigh A potential novel approach to bladder cancer imaging is FDG-PET/MRI, which combines the strengths of both modalities: the superior contrast resolution and multiparametric assessment with MRI and the metabolic assessment with PET. A pilot study with 22 FDG-PET/MRI examinations [42] found that FDG-PET/MRI had a higher accuracy than MRI alone for detecting bladder tumors (86% versus 77%), metastatic pelvic lymph nodes (95% versus 76%), and nonnodal pelvic malignancies (100% versus 91%).
Pretreatment Staging of Urothelial Cancer. A recent retrospective analysis by Chen et al [40] of 168 patients with pathologically confirmed NMIBC who underwent preoperative CTU were divided into low-, medium-, high-, and very-high-risk groups based on the European Society of Urology guidelines [22] and then further analyzed based on tumor size, location, number, and various tumor characteristics including size of base and perivesical stranding at diagnosis [40]. These data were then used to attempt to stratify patients at higher risk for recurrences, which is important because these recurrences can become MIBC and metastasize [41]. This was a preliminary study that demonstrated the feasibility of using preoperative CTU features to predict the risk stratification of NMIBC, but further validation in a larger population is needed. Combinations of CT features and other characteristics may further improve the performance of the model and provide more accurate information for patient evaluation. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is not ideal for evaluating the urinary collecting system because FDG is excreted through urine, but it can be useful in detecting distant metastases. Studies suggest that FDG-PET/CT may not be necessary for staging NMIBC because of a low likelihood of nodal or metastatic disease [22,23]. FDG-PET/MRI Skull Base to Mid-Thigh A potential novel approach to bladder cancer imaging is FDG-PET/MRI, which combines the strengths of both modalities: the superior contrast resolution and multiparametric assessment with MRI and the metabolic assessment with PET. A pilot study with 22 FDG-PET/MRI examinations [42] found that FDG-PET/MRI had a higher accuracy than MRI alone for detecting bladder tumors (86% versus 77%), metastatic pelvic lymph nodes (95% versus 76%), and nonnodal pelvic malignancies (100% versus 91%).