Pathological outcome for Chinese patients with low-risk prostate cancer eligible for active surveillance and undergoing radical prostatectomy: comparison of six different active surveillance protocols.

Introduction: Active surveillance is one of the therapeutic options for the management of patients with low-risk prostate cancer. This study compared the performance of six different active surveillance protocols for prostate cancer in the Chinese population. Methods: Patients who underwent radical prostatectomy for prostate cancer from January 1998 to December 2012 at a university teaching hospital in Hong Kong were reviewed. Six active surveillance protocols were applied to the cohort. Statistical analyses were performed to compare the probabilities of missing unfavourable pathological outcome. The sensitivity and specificity of each protocol in identifying low-risk disease were compared. Results: During the study period, 287 patients were included in the cohort. Depending on different active surveillance protocols used, extracapsular extension, seminal vesicle invasion, pathological T3 disease, and upgrading of Gleason score were present on final pathology in 3.3%-17.1%, 0%-3.3%, 3.3%-19.1%, and 20.6%-34.5% of the patients, respectively. The University of Toronto protocol had a higher rate of extracapsular extension at 17.1% and pathological T3 disease at 19.1% on final pathology than the more stringent protocols from John Hopkins (3.3% extracapsular extension, P=0.05 and 3.3% pathological T3 disease, P=0.03) and Prostate Cancer Research International: Active Surveillance (PRIAS; 8.0% pathological T3 disease, P=0.04). The Royal Marsden protocol had a higher rate of upgrading of Gleason score at 34.5% compared with the more stringent protocol of PRIAS at 20.6% (P=0.04). The specificities in identifying localised disease and lowrisk histology among different active surveillance protocols were 59%-98% and 58%-94%, respectively. The John Hopkins active surveillance protocol had the highest specificity in both selecting localised disease (98%) and low-risk histology (94%). Conclusions: Active surveillance protocols based on prostate-specific antigen and Gleason score alone or including Gleason score of 3+4 may miss high risk disease and should be used cautiously. The John Hopkins and PRIAS protocols are highly specific in identifying localised disease and low-risk histology.