Molecular aspects of bladder carcinoma part II. Molecular diagnostics

The current system of classifying bladder carcinoma by stage and histologic al grade is very useful, yet still has limited ability to predict the natur al history or treated natural history of a bladder tumor. Cystoscopy and ur ine cytology are currently considered the "gold standard" in the diagnosis and follow-up of bladder cancer. Classical urine cytology, however, at leas t in the diagnosis of G1-tumor, is characterized by a relatively low sensit ivity. In the last few years, investigation of the basic mechanisms involve d in carcinogenesis and tumor progression by molecular biology has provided a host of markers which are of potential diagnostic or prognostic value fo r bladder carcinoma. We provide a current, comprehensive review of the lite rature on bladder tumor markers and summerize their diagnostic and prognost ic potential. Conclusions: Under the premise that cystoscopy has never been subjected to evaluation, no diagnostic marker currently exists with a sensitivity and sp ecificity comparable to cystoscopy. The combined analysis of several tumor markers as in the Immunocyt test seems to be the most promising approach. I n the future these rather highly sensitive tests could replace cystoscopy o r prolong the intervals between cystoscopies in the follow-up of selected p atients. The literature suggests that no single marker is currently able to accurately predict the course of bladder tumors. A combination of prognost ic markers could predict which superficial tumors need an aggressive form o f therapy and which invasive tumors require adjuvant therapy. Altogether, t he most promising markers are, at this point, Ki-67 and p53 expression as w ell as matrixmetalloproteinase complex and angiogenesis.