[Bladder tumors and molecular markers. Current status and perspectives]

With 15,000 new cases each year, bladder tumors are the second leading urological cancer in France, after prostate carcinoma. In spite of advances in surgical techniques and therapeutic protocols based on trans-urethral resection associated with additive treatment (immunotherapy or endovesical chemotherapy), the natural course of superficial bladder tumors remains marked by two risks: recurrence and progression. In spite of the impressive efforts developed by molecular biologists searching for new specific markers, none of the markers can currently replace histological features such as stage and grade. Although detection of microsatellite instability is a promising approach, numerous difficulties limit the use of these markers and prevent their application in routine practice. Let us hope that the new techniques for tissue analysis such as DNA or tissue-arrays developed for simultaneous analysis of hundreds or even thousands of tumors will allow identification and validation of biological and even therapeutic markers. Among the various biological markers, only the proliferative index given by the expression of Ki67, the expression of p53 and EGFR have been examined in comparative studies. Ki67 seems to be the best marker for progression, its expression and the interpretation of results being more reproducible than for p53.