Pathological and oncological features of Korean prostate cancer patients eligible for active surveillance: analysis from the K-CaP registry

Background: A web-based multicenter Korean Prostate Cancer Database (K-CaP) was established to provide urologists with information on Korean prostate cancer (PCa) patients treated with radical prostatectomy (RP). We utilized the K-CaP registry to identify pathological features and oncological outcomes of Korean PCa patients eligible for active surveillance (AS). Methods: The K-CaP registry consisted of 6415 patients who underwent RP from May 2001 to April 2013 at five institutions. Preoperative clinicopathological data were collected to identify patients who were eligible for at least one contemporary AS protocol. Patients who had received neoadjuvant androgen deprivation therapy or a 5 alpha-reductase inhibitor, who had <10 total biopsy cores, or who had incomplete data were excluded. Biochemical recurrence (BCR) was defined as prostate-specific antigen (PSA) level >= 0.2 ng/ml following RP. Results: A total of 560 patients were identified, and the median follow-up period was 52.0 (interquartile range, 39.0-67.3) months. Pathologically insignificant PCa, defined as organ-confined disease with Gleason score <= 6 was observed in 314 (56.1%) patients. Pathological upgrading (Gleason score >= 7) and upstaging (>= pT3) were observed in 237 (42.3%) and 75 (13.4%) patients, respectively. Unfavorable disease (extracapsular extension, seminal vesicle invasion, or Gleason score >= 8) was observed in 85 (15.2%) patients. PSA density <= 0.2 ng/ml/cc and maximal single core involvement <= 20% were revealed as independent preoperative predictors of pathologically insignificant PCa. Conclusion: Contemporary Western AS protocols unreliably predict pathologically insignificant PCa in Korean men. Korean men may harbor more aggressive PCa features than Western men, and thus, a more stringent AS protocol is needed.