Oncological impact of neoadjuvant hormonal therapy on permanent iodine-125 seed brachytherapy in patients with low- and intermediate-risk prostate cancer

Objectives: To determine whether neoadjuvant hormonal therapy improves oncological outcomes of patients with localized prostate cancer treated with permanent brachytherapy. Methods: Between January 2004 and November 2014, 564 patients underwent transperineal ultrasonography-guided permanent iodine-125 seed brachytherapy. We retrospectively analyzed low- or intermediate-risk prostate cancer based on the National Comprehensive Cancer Network guidelines. The clinical variables were evaluated for influence on biochemical recurrence-free survival, progression-free survival, cancer-specific survival and overall survival. Results: A total of 484 patients with low-risk (259 patients) or intermediate-risk disease (225 patients) were evaluated. Of these, 188 received neoadjuvant hormonal therapy. With a median follow up of 71 months, the 5-year actuarial biochemical recurrence-free survival rates of patients who did and did not receive neoadjuvant hormonal therapy were 92.9% and 93.6%, respectively (P = 0.2843). When patients were stratified by risk group, neoadjuvant hormonal therapy did not improve biochemical recurrence-free survival outcomes in low- (P = 0.8949) or intermediate-risk (P = 0.1989) patients. The duration or type of hormonal therapy was not significant in predicting biochemical recurrence. In a multivariate analysis, Gleason score, pretreatment prostate-specific antigen, clinical T stage, and prostate dosimetry, primary Gleason score and positive core rate were significant predictive factors of biochemical recurrence-free survival, whereas neoadjuvant hormonal therapy was insignificant. Furthermore, neoadjuvant hormonal therapy did not significantly influence progression-free survival, cancer-specific survival or overall survival. Conclusions: In patients with low- or intermediate-risk disease treated with permanent prostate brachytherapy, neoadjuvant hormonal therapy does not improve oncological outcomes. Its use should be restricted to patients who require prostate volume reduction.