Predictors of secondary treatment following biochemical recurrence after radical prostatectomy: Results from the Shared Equal Access Regional Cancer Hospital database

OBJECTIVE To investigate the predictors of secondary treatment for recurrent prostate cancer after radical prostatectomy (RP) among subjects from the Shared Equal Access Regional Cancer Hospital (SEARCH) database. PATIENTS AND METHODS We used Kaplan-Meier curves and Cox proportional hazard models to identify factors associated with time to secondary treatment and type of secondary treatment received among 697 men who developed biochemical recurrence (BCR) after RP. RESULTS During a median follow-up of 45 months after BCR, 357 men received salvage treatment. The 1-, 3-, and 5-year risk of receiving any salvage treatment was 29% (95% confidence interval (CI) 26-33%), 48% (95%CI 44-52%), and 53% (95%CI 49-57%), respectively. In multivariate analysis, more recent year of recurrence, centre, shorter disease-free interval, and pathological high-grade disease (Gleason 8-10) predicted increased risk of salvage treatment (all P < 0.01). Predictors of specifically receiving radiotherapy were shorter disease-free interval, centre, and more recent year of BCR (all P < 0.001). Predictors of specifically receiving hormonal therapy were shorter disease-free interval, more recent year of BCR, centre, high Gleason score, and higher tumour stage (all P < 0.05). In a subset analysis of men with available prostate-specific antigen doubling time (PSADT) data, shorter PSADT predicted receipt of any salvage treatment as well as radiation and hormonal therapy separately. CONCLUSIONS Among men who recur after RP, salvage treatment was associated with disease severity, centre and year of BCR; patient-specific factors (race, body mass index and age) were not predictive of secondary treatment. Although patients are being treated more aggressively in contemporary years, the affect on long-term survival is unknown.