Impact of supplemental external beam radiotherapy and/or androgen deprivation therapy on biochemical outcome after permanent prostate brachytherapy

To evaluate the impact of supplemental external beam radiotherapy (EBRT) and/or androgen deprivation therapy (ADT) on 8-year biochemical outcome after permanent prostate brachytherapy. Between April 1995 and January 2001, 668 consecutive patients underwent brachytherapy using either 103Pd or 125I for clinical Stage T1b–T3aNxM0 (2002 American Joint Committee on Cancer) adenocarcinoma of the prostate gland. No patient underwent seminal vesicle biopsy or pathologic lymph node staging. The median follow-up was 58.6 months. Biochemical progression-free survival was defined by the American Society for Therapeutic Radiology and Oncology consensus definition. The clinical, treatment, and dosimetric parameters evaluated for biochemical progression-free survival included supplemental EBRT, ADT, patient age, clinical stage, Gleason score, preimplant prostate specific antigen (PSA), risk group, percentage of positive biopsies, isotope used, prostate volume, planning volume, percentage of target volume receiving 100%, 150%, and 200% of prescribed dose, minimal percentage of dose covering 90% of target volume, tobacco status, hypertension, and diabetes. For the entire group, the actuarial 8-year biochemical progression-free survival rate was 98.2%, 98.4%, and 88.2% for low-, intermediate-, and high-risk patients, respectively, with a median PSA level of