Predictors of Progression to Castration-resistant Prostate Cancer After Radical Prostatectomy in High-risk Prostate Cancer Patients.

Abstract

To examine the specific time frame and identify associated risk factors from commencement of hormonal therapy to the onset of castration-resistant prostate cancer among patients who have developed biochemical recurrence following radical prostatectomy. We retrospectively reviewed the records of 92 patients who developed biochemical recurrence and received hormonal therapy as initial salvage treatment after radical prostatectomy for high-risk localized prostate cancer from 2005 to 2021. The castration-resistant prostate cancer-free survival rates from the commencement of salvage hormonal therapy were analyzed using log-rank methods. Cox proportional hazard regression was performed to analyze the risk factors associated with acquiring castration resistance. The patients were stratified based on those risk factors. During a median follow-up duration of 57 months, 24 (26.1%) patients developed castration-resistant prostate cancer. The 5- and 10-year castration-resistant prostate cancer-free survival rates were 73.6% and 54.5%, respectively. A multivariate analysis showed that Grade Group of 5 and prostate-specific antigen doubling time at biochemical recurrence of ≤3 months were independent predictors of castration-resistant prostate cancer. The 5-year castration-resistant prostate cancer-free survival rates in the low- and high-risk groups, stratified according to the aforementioned factors, were 85.4% and 47.6%, respectively. Patients in high Grade Group and short prostate-specific antigen doubling time after radical prostatectomy are more likely to develop resistance to salvage hormonal therapy.