103P d brachytherapy and external beam irradiation for clinically localized, high-risk prostatic carcinoma

Abstract

Purpose : To summarize biochemical failure rates and morbidity of external irradiation (EBRT) combined with palladium ( 103Pd) boost for clinically localized high-risk prostate carcinoma. Methods and Materials : Sevently-three consecutive patients with stage T2a-T3 prostatic carcinoma were treated from 1991 through 1994. Each patient had at least one of the following wisk factors for extracapsular disease extension: Stage T2b or greater (71 patients), Gleason score 7–10 (40 patients), prostate specific antigen (PSA) >15 (32 patients), or elevated prostatic acid phosphatase (PAP) (17 patients). Patients received 41 Gy EBRT to a limited pelvic field, followed 4 weeks later by a 103Pd boost (prescription dose: 80 Gy). Biochemical failure was defined as a PSA greater than 1.0 ng/ml (normal < 4.0 ng/ml). Patients whose PSA was still decreasing at the last follow-up were censored at that time. Patients whose PSA plateaued at a value greater than 1.0 were scored as failures at the time the PSA first plateaued. Results : The overall, actuarial freedom from biochemical failure at 3 years after treatment was 79%. In Cox proportional hazard multivariate analysis, the strongest predictor of failure was elevated acid phosphatase ( p = 0.04), followed by PSA ( p = 0.17), stage ( p = 0.17), Stage ( p = 0.23). Treatment-related morbidity was usually limited to temporary, RTOG Grade 1–2 urinary symptoms. One patient, who had both a transurethral incision of the prostate (TUIP) and a transurethral resection of the prostate (TURP), developed low-volume urinary incontinence. The actuarial potency rate at 3 years after implantation was 77% for 46 patients who were sexually potent prior to implant. Conclusion : Biochemical freedom from failure rates following combined EBRT and 103Pd brachytherapy for clinically localized,, high-risk prostate cancer compare favorably with that reported conventional dose EBRT alone. Morbidity has been acceptable.