Between 1998 and 2009, 229 patients were treated with HDR brachytherapy followed 3 weeks later by supplemental EBRT. The HDR brachytherapy boost consisted of three fractions of 192Ir (5.5-7.5 Gy per fraction), and EBRT consisted of intensity-modulated radiotherapy delivering an additional 45.0-50.4 Gy directed to the prostate gland and seminal vesicles. Median follow-up was 61 months.
Seven-year PSA relapse-free survival for low-, intermediate-, and high-risk patients were 95 % , 90 % , and 57 % , respectively (p < 0.001). Among high-risk patients treated with biological equivalent doses in excess of 190 Gy, 7-year PSA relapse-free survival was 81 % . In multivariate analysis, Gleason scores of ¡Ý8 predicted for increased risk of biochemical failure, whereas the use of short-term neoadjuvant androgen deprivation therapy did not influence tumor-control outcomes even among intermediate- or high-risk patients. Seven-year incidence of distant metastases for low-, intermediate-, and high-risk patients were 5 % , 3 % , and 17 % , respectively. Seven-year incidence of late Grade 2 and 3 genitourinary toxicities were 22.1 % and 4.9 % , respectively and the 7-year incidence of Grade 2 and 3 gastrointestinal toxicities were 1 % and 0.4 % , respectively.
HDR prostate brachytherapy in conjunction with supplemental EBRT results in excellent biochemical relapse-free survival rates with a low incidence of severe late genitourinary or gastrointestinal toxicities. The use of short-term neoadjuvant androgen deprivation did not influence long-term biochemical tumor control in this cohort.