Effects of neoadjuvant hormonal therapy on prostate biopsy results after (125)I and (103)Pd seed implantation.

Abstract

Background: Androgen ablation may improve the efficacy of radiation therapy.

Patients and methods: A total of 296 patients who had either (125)I (206; 70%) or (103)Pd (90; 30%) transperineal prostate brachytherapy (no external-beam radiation) had routine transrectal ultrasound-guided needle biopsy (minimum six cores) 2 years after treatment without regard to disease status. Neoadjuvant hormonal therapy (NHT: leuprolide acetate and flutamide) was used in 115 patients (39%) for 3 months prior to and 3 months after the implant.

Results: Of the 296 patients, 30 (10%) had positive prostate biopsies. Biopsies were positive in 4 of 115 (3.5%) v 26 of 181 (14%) of those who received or had not received NHT, respectively (P = 0.002). When patients were separated into low risk (PSA < or = 10 ng/mL, stage < or = T(2a), and Gleason score < or = 6) and high risk (all others), it was seen that low-risk patients did not benefit from NHT (3.8 v 7.7% positive biopsy rate; P = 0.5) whereas high-risk patients did (3.4% v 21.1%; P = 0.003).

Conclusion: Prostate brachytherapy yields high negative biopsy rates (90%) 2 years after treatment. Neoadjuvant hormonal therapy can improve the local control rates (as determined by biopsy) in patients undergoing (125)I or (103)Pd seed implantation. These results are most significant for patients who present with PSA >10 ng/mL, stage > or = T(2b) diseases, or Gleason score > or = 7 (high-risk status).