Patients in this study had to have tumors greater
Patients in this study had to have tumors greater than or equal to 25 cm2. Pilepich et al reported the 8- year update and, as with the previous RTOG study, a significant difference in local failure continued between the two arms (RT + H versus RT alone, P = 0.004). Eight-year local failure rates were 32% and 43%, respectively, between the two groups. An improvement in progression- free survival for the RT + H patients (P = 0.0019) and distant failure (RT + H versus RT alone, P = 0.04) was observed. The apparent benefit of combined androgen suppression and EBRT has led several investigators to examine whether androgen suppression when combined with prostate brachytherapy confers a disease-free survival benefit. D’Amico et al evaluated 1872 men treated with radical prostatectomy or brachytherapy with or without neoadjuvant androgen deprivation or conformal EBRT; 216 were treated with prostate brachytherapy. Of these, 66 had an implant alone and 152 had an implant with androgen suppression. The androgen suppression was 3 months of neoadjuvant luteinizing hormone-releasing hormone agonist preceded by 7 to 10 days of a nonsteroidal antiandrogen. The patients were stratified according to risk groups and Gleason scores. No differences between the two groups of patients were seen except in those patients with Gleason 7. Stone and Stock evaluated 152 men with moderate-risk disease treated with prostate brachytherapy. Seventy of the one hundred and fifty-two men received 5 months of neoadjuvant and adjuvant hormonal deprivation beginning 3 months before the implant. The 4- year, disease-free survival was improved in the androgen-treated group; however, the follow-up was relatively short. Based on a review of the literature, Lee concluded that little evidence exists to support improved disease-free survival in men treated with a combination of androgen suppression and prostate brachytherapy. He has speculated that the possible reasons for this lack of effect may be related to the fact that most men treated with prostate brachytherapy do not have clinical evidence of extracapsular disease, and therefore represent a different population of men than those evaluated in the combination EBRT and androgen suppression trials. Furthermore, the androgen suppression administered in the prostate brachytherapy trials is substantially shorter than the duration of androgen deprivation in trials showing a benefit. Brachytherapy has been given in combination with EBRT. This generally has been reserved for patients with higher stage or grade disease. Radge et al evaluated 229 patients who received I-125 permanent prostate brachytherapy, and divided them into two treatment groups. The first group was treated with an implant alone, whereas the second group was treated with combined EBRT of 45 Gy to the prostate and pelvis followed by an implant 2 weeks after the completion of the EBRT. The 82 patients in this group had higher-risk disease based on clinical stage and Gleason grade. bNED control at 10 years was 79%. E.M. Horwitz et al / Urol Clin N Am 30 (2003) 737–750 739 Grado et al evaluated 490 patients with T1–T3 prostate cancer treated with I-125 and Pd- 103 brachytherapy. Seventy-two patients with T2b or greater disease received adjuvant EBRT. The authors found no evidence of incremental benefit with the addition of EBRT. Rates of disease-free survival in the implant alone and the combination groups were not significantly different, even in multivariate models taking into account differences in disease stage. However, the authors did note that a 72% actuarial, 5- year, disease-free survival was achieved in the combined group, despite the more advanced stage of these patients. The American Brachytherapy Society (ABS) currently recommends adjuvant EBRT for those patients who are felt to be at significant risk for extraprostatic extension. Some authors have advocated trimodality therapy including implant, EBRT, and neoadjuvant hormonal deprivation. Stock and Stone treated 301 patients with T1–T3 prostate cancer with brachytherapy alone or combined with hormonal therapy or EBRT. Forty of these patients were deemed high risk based on a PSA level greater than 15 ng/mL, Gleason score greater than or equal to 8, clinical stage T2c–T3, or positive seminal vesicle biopsy. This group was given combination brachytherapy, EBRT, and 9 months of hormonal therapy. The 3-year biochemical freedom from failure rate in this group was 71%.
