This study seeks to determine the role of automated flow cytometry in detecting transitional cell carcinoma of the bladder, in monitoring its response to therapy, and in determining the malignant potential of individual tumors. Efforts will be directed toward: 1. Improving sample preparation, staining and storage of bladder washing and urine specimens. (This will include exploring protocols for fixation and staining as well as nuclear isolation.) 2. Using paraffin-embedded pathology specimens in retrospective studies for bladder cancer patients whose clinical outcome is known. (This will include evaluating DNA histograms for DNA index, percent cycling cells, statistical spread including SD and CV, and comparing the histogram parameters to the known clinical course of the disease. In addition, several choices of second parameters will be explored to enhance diagnostic accuracy. These will include the use of antibodies (both polyclonal and monoclonal) directed against oncogene products as well as monoclonal antibodies raised against bladder cancer cells.) 3. Using freshly obtained bladder tissue for ongoing DNA flow cytometry studies comparing the histogram parameters mentioned above to the clinical course and pathological grade and stage of the tumor. 4. Studies of oncogene expression as determined by levels of specific oncogene-derived products to use in (1) semiquantitative immunoperoxidase assays and (2) the two-parameter studies described above. 5. Developing improved histogram analysis protocols and establishing an appropriate data base for correlating the data obtained to the clinical course of the disease in order to determine which of the parameters studied, including clinical and pathological descriptions, are predictive of single tumor occurrence of recurrent tumors of the same stage, or tumor progression. Furthermore, we will attempt to decide which of these parameters best predicts which lesions will be responsive to chemotherapy.