Bladder cancer: natural history, tumor markers, and early detection strategies.

Transitional cell bladder carcinoma is characterized by a dichotomous, multichronotopic natural history. Low and moderate grade Ta lesions frequently recur, yet rarely invade, and carry an excellent prognosis with currently available treatments. High grade Ta lesions, tumors with lamina propria invasion (T1), and carcinoma in situ often progress to invasive disease, at which time overall prognosis is significantly decreased, despite various treatment alternatives. Although early detection of bladder tumors, prior to muscle invasion, should vastly improve our ability to save both bladders and lives, current methods of detection are neither sufficiently sensitive nor specific. Tumor marker analysis is an exciting new frontier in bladder cancer evaluation, and may have important applications to early detection strategies, in combination with simple hematuria testing and other selected noninvasive screening methods.