Incidental prostate cancer in Asian men: high prevalence of incidental prostatic adenocarcinoma in Chinese patients undergoing radical cystoprostatectomy for treatment of bladder cancer and selection of candidates for prostate-sparing cystectomy.

Abstract

Previous studies report a low prevalence of incidental prostate cancer in Chinese patients (3-7%). We evaluated incidental prostatic adenocarcinoma (PCa) and urothelial carcinoma (UCa) involvement of the prostate in cystoprostatectomy specimens. We analyzed 340 cystoprostatectomy specimens from patients who underwent radical cystoprostatectomy for the treatment of bladder cancer in China from 2004 to 2014. None of the patients had known prostate cancer prior to cystoprostatectomy. Overall, 180 (53%) patients had either PCa or UCa in the prostate. We found that 95 (28%) had PCa and 115 (34%) had UCa involvement of prostate. The rate of incidental prostate cancer was 21% and 31%, respectively, from two study periods (2004-2008 and 2009-2014). Among the 95 patients with PCa, 19 (20%) had Gleason score of ≥7, nine (10%) had PCa tumor volume >0.5 cc, and eight (8.4%) had extracapsular extension. Of the 115 with prostatic UCa, 61 had prostatic urethra and/or periurethral prostatic duct involvement only, while 54 had prostatic stromal invasion. Age (odds ratio [OR] = 1.04, P = 0.001), increasing stage of bladder tumor (OR = 1.28, P = 0.005), multifocal tumors of bladder (OR = 3.22, P < 0.001), carcinoma in situ (CIS) in the bladder (OR = 5.52, P < 0.001), and bladder neck involvement (OR = 6.12, P < 0.001) were strongly associated with prostatic UCa. The rate of incidental PCa in cystoprostatectomy specimens in China has increased over the last decade. Patients with advanced age, elevated serum PSA level, advanced bladder tumor stage, multifocal bladder tumors, CIS in the bladder, and tumor location at the bladder neck should be excluded as candidates for prostate-sparing cystectomy.