Prostate Cancer With Large Glands Treated With 3-Dimensional Computerized Tomography Guided Pararectal Brachytherapy: Up to 8 Years of Followup

Abstract
Purpose: We report post-brachytherapy results in patients with cancer in a large prostate. Materials and Methods: From June 1, 1994 to June 30, 2000, 331 consecutive patients with a large prostate of 50 to 180 cm.3 (median 69) were treated with 3-dimensional computerized tomography guided brachytherapy. Patient age was 42 to 90 years (median 69). Of these patients 327 were available for followup for 2 to 8 years (median 4.5). Patients were stratified according to risk profile. The high risk group had 1 or more high risk factors (prostate specific antigen [PSA] greater than 20 ng./ml., Gleason greater than 7, stage T2b, T3a or T3b) or 2 intermediate risk factors (PSA 10 to 20 ng./ml. and Gleason 7). The high risk group was further stratified into subgroups with a similar risk profile. The intermediate risk group had only 1 high risk factor (PSA 10 to 20 ng./ml. or Gleason 7). The low risk group had PSA less than 10 ng./ml., Gleason less than 7 and stage T1a, b, c or T2a. A dose of 144 Gy. with 125I or 120 Gy. with 103Pd was achieved in 90% to 100% of the target. A total of 31 patients (9%) had previously undergone transurethral resection and 198 (60%) were treated with 3 months of neoadjuvant androgen ablation. Results: Biochemical disease-free survival was achieved in 90% of the 182 patients at high risk, 96% of the 52 at intermediate risk and 99% of the 93 at low risk. Seven patients (2%) required catheterization during year 1 for urinary retention, 11 (3%) required transurethral prostate resection 1 to 4 years after implantation, 3 patients (1%) had grade 1 or 2 incontinence after repeat transurethral prostate resection and 4 (1%) had grade 3 or 4 rectal complications. Conclusions: The 3-dimensional computerized tomography guided pararectal permanent implant results in a high level of biochemical control with low morbidity at 2 to 8 years in patients with prostate cancer who have a large prostate. There was less favorable biochemical control in patients with PSA greater than 20 ng./ml., Gleason 7 or greater and seminal vesicle invasion.