Deferred radical prostatectomy in patients who initially elected for active surveillance: a multi-institutional, prospective, observational cohort of the PRIAS-JAPAN study

Background: This study aimed to evaluate the pathological findings and oncological outcomes of deferred radical prostatectomy in patients who initially elected for active surveillance in a Japanese cohort. Methods: We retrospectively analyzed data collected from a multi-institutional prospective observational cohort of the Prostate Cancer Research International: Active Surveillance-JAPAN study between January 2010 and September 2020. Triggers for radical prostatectomy were disease progression based on pathological findings of repeat biopsy and patients’ request. The primary end point was evaluation of prostate-specific antigen recurrence-free survival. Secondary end points were overall survival and comparison of pathological and oncological outcomes between patients stratified into immediate or late radical prostatectomy group by time to radical prostatectomy. Results: Overall, 162 patients (15.7%) with prostate cancer underwent initial active surveillance followed by radical prostatectomy. The median time to radical prostatectomy was 18 months (interquartile range 14–43.3), and the median postoperative follow-up was 32 months (interquartile range 14–57.5). Prostate-specific antigen recurrence was observed in eight patients (4.9%). The 3-year prostate-specific antigen recurrence-free survival rate was 96.9%. The 5-year overall survival rate was 100%; however, one patient died of another cause. There were no significant differences in pathological findings between immediate and late radical prostatectomy groups. No significant difference in prostate-specific antigen recurrence-free survival was found between the two groups (log-rank p = 0.34). Conclusions: Radical prostatectomy after active surveillance, as an initial treatment option, does not lead to loss of curative chances in Japanese patients with early-stage prostate cancer in the short follow-up period.