Change in the risk stratification of prostate cancer after Slide Review by a uropathologist: the experience of a reference center for the treatment of prostate cancer

Introduction Brachytherapy is an option for treating low-risk prostate cancer (PC). Biochemical control of low-risk disease can reach 95%. The practice advocated is that a review of prostate biopsies should be mandatory before choosing the best treatment for patients with PC. Our objective was to evaluate the change in PC risk after review of a prostate biopsy by an experienced uropathologist at a reference hospital. Materials and Methods Between December 2003 and August 2012, 182 men were referred to our institution for brachytherapy to treat PC. Their slides were reviewed by the same uropathologist. Results and Discussion Classification risk disagreement occurred in 71 (39%) cases, including one in which no tumor was observed. The main cause of risk change was related to the Gleason score (GS), with 57 (81.4%) cases upgraded to GS 7 or 8. Tumor volume was also compared, although only the number of fragments was reported in most original reports. The concordance of the number of cores affected by tumor was 43.9%, and in 49% of the cases, the number was decreased by the uropathologist. Perineural invasion (PNI) was reported in one quarter of original reports, and the agreement was 58%. Conclusion Slide review by an uropathologist remains essential at reference radiotherapy centers for the treatment of PC. The change in PC risk evaluation is mainly due to the GS, but tumor volume and PNI, which are important for the characterization of tumor aggressiveness, are also misinterpreted and could drive a change in the therapy choice.