Predictive value of DNA ploidy in bladder cancer treated with preoperative radiation therapy and cystectomy.

The predictive value of flow cytometric DNA analysis of cells from bladder washings was evaluated in 43 patients with muscle-invasive or recurrent superficial bladder cancer treated with preoperative radiotherapy and cystectomy. There was no correlation between ploidy status of the primary tumour and survival, neither was there any correlation between ploidy and the occurrence of residual tumour in the cystectomy specimens. Patients without residual tumours in the cystectomy specimen had significantly longer survival time than those with residual tumours. Concomitant carcinoma in situ was correlated with better survival, which is surprising, considering the malignant potential of this lesion. In this study DNA ploidy did not predict tumour response to radiotherapy nor was it of any prognostic significance.