Statistical analysis of recurrent factors in superficial bladder cancer. Natural history of superficial bladder cancer

Abstract

Three hundred thirty-six patients with superficial bladder cancers underwent their initial surgery at the Department of Urology of Okayama University School of Medicine from 1961 to 1985. They have been followed-up until December 1988 (the median: 68 months). Among the 336 cases, excluding 9 cases which were treated initially with total cystectomy or incomplete resection, the remaining 327 cases were reviewed in order to study the pattern of their local recurrences in the bladder. Major factors affecting recurrences of superficial bladder cancer were evaluated by the multivariate analysis using Cox's proportional hazard model. The examined factors included age on admission, sex, tumor's number, size, stage, histological grade and shape, operative method, intravesical chemotherapy, systemic chemotherapy, radiotherapy, frequency of recurrences and the date of operation. During the follow-up period, 179 cases out of the 327 cases did not show any recurrences. The remaining 148 cases recurred from once to 11 times, therefore, a total number of recurrences was counted to be 406. In the 406 recurrences, 338 recurrences were treated by TUR, SVR, or SR. The remaining 68 recurrences were treated with total cystectomy or untreated. Fifty-seven cases out of the 148 cases demonstrated recurrences more than 3 times. Only 4 cases were free from recurrences more than 24 months following the surgery for their last recurrences. The analysis in the 327 primary cases showed that the number of tumors was the most important factor. On the other hand the analysis in 338 recurrences showed that the second most important factor was the frequency of recurrences, following the number of tumors.(ABSTRACT TRUNCATED AT 250 WORDS)