Computer tomography and magnetic resonance imaging in the evaluation of bladder cancer.

Bladder cancer is the most common of the malignant urothelial tumours accounting for 6% of all male cancers, and CT and MRI are both firmly established as valuable methods of staging. Although MRI has important advantages compared with CT, the results of studies carried out in the 1980's comparing both techniques for staging showed a similar accuracy range (64-92% for CT and 72-96% for MRI). However, during recent years, advances in technology in MRI and the use of intravenous contrast medium have improved results, particularly in the evaluation of early lesions. The advantage and limitations of both techniques will be discussed in relation to staging of primary tumour and lymph nodes. Imaging is also important for the reassessment of patients following treatment to monitor therapeutic response and to identify recurrence. MRI may be superior to CT for the distinction of fibrosis and oedema from tumour following radiotherapy, but both techniques appear to be equally accurate in the evaluation of chemotherapeutic response in advanced invasive disease.