Bladder transitional cell carcinomas: A comparative study of washing and tumor bioptic samples by DNA flow cytometry and FISH analyses

Objective and Methods: We com pa red information obtained from samples of tu mor biopsy and bladder washing to evaluate the representatives of the latter type of sampling. Both types of samples from 44 cases of superficial bladder TCCs and one papilloma were analyzed by FCM, to evaluate cellular DNA content, and FISH, to detect numerical aberration of chromosome 9. Results: The use of both tumor and washing samples by FCM and FISH analyses evidenced alterations in 95% of cases. FCM evidenced higher aneuploid frequency in bladder washing than in bioptic specimens. In bladder washing, FISH analysis showed higher frequency of monosomy and lower frequency of trisomy than in biopsy. No correlation was found between histological grade and centromeric chromosome 9 loss while correlation was evidenced with centromeric 9 gain. Conclusion: Irrigation specimens, analyzed by FCM and FISH, can complement information obtained by biopsy in cytodiagnosis and follow-up of patients with bladder TCC. Copyright (C) 2000 S. Karger AG, Basel.