Risk of concomitant carcinoma in situ determining biopsy candidates among primary non-muscle-invasive bladder cancer patients: Retrospective analysis of 173 Japanese cases

Objectives:   To determine candidates for bladder biopsies among Japanese primary non-muscle-invasive bladder cancer patients according to the risk of concomitant carcinoma in situ (CIS).
Methods:   Between January 1992 and August 2006, 173 primary non-muscle-invasive bladder cancer cases underwent transurethral resection of the bladder tumor with bladder biopsies for the detection of CIS. Correlations between biopsy results and preoperative/pathological features were retrospectively analyzed.
Results:   Positive cytology was statistically associated with the presence of concomitant CIS in multivariate analysis ( P  < 0.01). Abnormal cystoscopic appearance outside the tumor almost achieved statistical significance in multivariate analysis among preoperative factors ( P  = 0.06). In our series, one (12.5%) of eight low-risk, 18 (24.7%) of 73 intermediate-risk and 41 (59.4%) of 69 high-risk cases had CIS in normal-looking sites, respectively. In cases with a single papillary tumor and negative cytology, one of 16 (6.3%) had concomitant CIS in their biopsy specimens at the normal-looking sites.
Conclusions:   All non-muscle-invasive bladder cancer patients with positive cytology are candidates for additional random biopsies. Targeted biopsies should be performed for all suspicious areas in the bladder mucosa. Random biopsies should be considered in cases with the macroscopic types of cancer for predicting intermediate- and high-risk cancer.