Local chemotherapeutic effects in bladder cancer demonstrated by selective sampling and flow cytometry

A method is described by which the effect of intravesical chemotherapy can be monitored. Cytological samples obtained selectively during treatment were used for morphological and flow cytometric studies, and isoantigen (A, B and H) assessment in 2 patients with urothelial cancer. With flow cytometry even small aneuploid populations in the urothelium could be identified. From the histograms the urothelium was seen to contain 2 different cell populations: 1) diploid and 2) aneuploid. The ratio between aneuploid and diploid cells decreased significantly during treatment. Treatment was continued until no evidence of aneuploid cells could be identified in the histograms. Thus, it is demonstrated that intravesical chemotherapy for certain types of bladder cancer can eradicate the aneuploid cell population. A good correlation was found between cytological studies and flow cytometric measurements. Isoantigen assessment was done in the cell suspension used for morphological and flow cytometric studies. Isoantigen assessment also showed loss of antigens after completion of treatment, indicating that the diploid population was not normal biologically. Thus, 3 parameters can be correlated and related also to topography.