The p53 tumor suppressor gene regulates many physiologic pathways that are important in the development of cancer and is the gene most frequently observed to be mutated in metastatic cancers. As a result, p53 mutations in cancer cells indicate that the tumor containing such p53 mutated cells is at high risk for disease progression to a higher clinical stage and/or grade. P53 mutated cancers are also more likely to recur after initial treatment than p53 wild type cancers and respond differently to some therapies. This project consists of a combination of clinical trials and programs of incremental improvement that seek to further develop and validate a robust commercially viable clinical assay to detect p53 gene mutations in bladder cancers cells that are exfoliated into the lumen of the bladder and collected in bladder cytology specimens. The successful completion of this phase II SBIR will change the way bladder cancer patients with stage T1 or greater disease are managed. The improvements in technology delivery and the expanded prospective and retrospective clinical trials will validate both the technology and its clinical utility to assess patient prognosis. These achievements will, in turn, direct patients to their most effective primary and adjuvant therapies. PROPOSED COMMERCIAL APPLICATION: The work proposed in this phase II SBIR grant application will further facilitate the acceptance and adoption of this test by urologists as a tool to be used in managing bladder cancer patients. Thus, the work proposed is also essential for the commercial success of this project at UroCor. The total p53 mutation detection market for bladder cancer prognosis is roughly 60,000 specimens/ year with a market approaching $15 million. Cost savings to the medical community due to more effective treatment of bladder cancer is significantly greater.