[Clinical analysis of multiple primary cancers associated with bladder cancer].

Among 321 bladder cancer cases from 1975 to 1989, 43 cases (13.4%) were found to have multiple primary cancers (MPC) and 278 cases without MPC (86.6%). These two groups were compared with regard to their clinical and pathological features. Mean age of patients when the bladder cancer was diagnosed was 68.9 +/- 8.9 in MPC cases and 65.7 +/- 12.3 (mean +/- S.D.) in cases without MPC. The male to female ratio was 3.8 to 1 and 2.6 to 1, respectively. The common sites of MPC were the lung, stomach and rectum, all of them being the organs often involved with cancer. Prostatic cancers in eight of 12 MPC cases were incidentally found in total cystectomy specimens. The sites of the synchronous and metachronous MPC involving lung, stomach and rectum cancers showed relatively even distribution. In males, the most common synchronous MPC included prostatic cancer, but in females, the diagnosis of uterine cancer tended to be made prior to the diagnosis of bladder cancer. In two cases, there was a strong suspicion that the therapy for the first cancer contributed to the occurrence of the second cancer. In the present study, no significant differences were noted with regard to clinicopathological characteristics of bladder cancer between the group with MPC and that without MPC. The five years survival rates from the beginning of bladder cancer treatment were 48.8% and 64.9%, respectively, indicating that the prognosis of the MPC cases was significantly worse (p less than 0.05) than that of cases without MPC. The most common cause of death in MPC cases was due to cancers other than bladder (36%).(ABSTRACT TRUNCATED AT 250 WORDS)