High proportion of clinically significant prostate adenocarcinomas in radical cystoprostatectomy specimens following complete prostate sampling.

Abstract

Clinically silent prostate adenocarcinoma may be detected as an incidental finding in radical cystoprostatectomy specimens. In previous studies, there have been major inconsistencies, both in the incidence of occult prostate adenocarcinoma, ranging from 2% to 60% of cases in reported series, and their significance in a clinical context. Much of the conflicting data in earlier studies relate ​to methodological issues such as small sample size, incomplete sampling of the prostate and lack of central review of pathological material. In this study, we have reviewed a series of 261 patients who underwent cystoprostatectomy for urothelial carcinoma, between the inclusive years 2010 and 2022, in order to determine the incidence and clinical significance of any prostate carcinomas discovered as part of the histological examination. All prostate glands in the series were fully embedded with sections taken from each block, and all cases were independently reviewed. The series contained 140 occult carcinomas, with the distribution according to patient age being 40-49 years (3 cases), 50-59 years (11 cases), 60-69 years (48 cases), 70-79 years (67 cases) ​and 80-89 years (11 cases). Within the age cohorts of 50-59 years, 60-69 years and 70-79 years, 34.1%, 53.9% and 57.7% of prostates, respectively, had prostate adenocarcinoma. Division of tumours according to Gleason score showed 3+3=6 (31.4%), 3+4=7 (47.9%), 4+3=7 (10%), 3+4=7 tertiary 5 (3.6%), 4+5=9 (5%) and 5+4=9 (2.1%). Clinically significant features were a Gleason score >6 in 68.8% of cases ​and a tumour volume >0.5 ​cm³ in 37.1% of cases. Both features were present in 37.1% of cases. Extension beyond the prostate was seen in nine cases. Our series shows that prostate adenocarcinoma is a common incidental finding in patients undergoing radical cystoprostatectomy, with many tumours having features associated with more aggressive disease. These results suggest that clinical assessment for prostate cancer and pre-operative multiparametric magnetic resonance imaging of the prostate should be undertaken, especially for patients in whom a more conservative surgical approach is planned.