Early experience of brachytherapy for patients with high-risk prostate cancer

We retrospectively evaluated 40 patients with high-risk prostate cancer who underwent 125I prostate brachytherapy in our institute. Thirty-six patients were treated with a combination of 45 Gy of external beam radiation therapy (EBRT) as well as brachytherapy. Follow-up visits were made 1 and 3 months after seed implantation and at 3-month intervals thereafter. The mean number of implanted seeds was 60 (range, 30-80). The prescribed dose was 144 Gy in those undergoing monotherapy of seed implantation and 105 Gy in those also undergoing EBRT. The median serum prostate-specific antigen value was 13.5 ng/ml (range, 4.1-182.8). According to the Gleason grading system, 7, 26 and 7 patients were classified as Gleason score 7, 8 and 9, respectively. Twenty-one patients received neoadjuvant hormone therapy with luteinizing hormone-releasing hormone agonist prior to seed implantation for a median of 8 months (range, 2-32). No patients received hormone therapy after radiation therapy. PSA relapse was seen in 2 patients (5%) within 1 year after seed implantation with osseous metastases, while 38 patients (95%) showed no recurrence. There were no patients who had Grade 3 genitourinary toxicity. In conclusion, a combination of EBRT plus brachytherapy is a possible treatment option for high-risk prostate cancer patients without high-grade toxicity. (author)