PET/CT and MRI in Bladder Cancer.

Bladder Cancer (BCa) is the most common malignancy arising from the urinary tract. One of the mainstays of diagnosis, staging, and therapeutic decision-making for BCa is accurate and appropriate imaging. The ability to identify metastatic disease preoperatively is of utmost importance in determining treatment. Advances in standard cross sectional imaging techniques like Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) have improved imaging of bladder cancer. Over the last decade, 18F-fluorodeoxyglucose (FDG) Positron Emission Tomography (PET) in combination with CT (18F-FDG PET/CT) has become an important non-invasive imaging modality for the preoperative staging of various malignancies. 18F-FDG PET/CT is useful for detection of metastatic disease in BCa, but the ability to detect primary bladder wall lesions remains to be elucidated. To overcome the problem with urinary excretion of 18F-FDG, new PET tracers are being tested. MRI is an accurate technique for the local staging of BCa due to its superior spatial and contrast resolution. Anatomical MRI has a modest utility in NM-staging of BCa. However, incorporation of functional MR techniques, such as diffusion weighted MRI can improve the results for lesion detection and staging and multi-parametric MRI`s role is yet to be explored widely. The aim of this review is to present the recent advances in PET/CT and MRI in BCa, with particular focus on improvements in staging.