PURPOSE:A Phase I/II protocol was conducted to examine the toxicity and efficacy of the combination of intensity-modulated radiation therapy (IMRT) with a single-fraction high-dose-rate (HDR) brachytherapy implant.
METHODS AND MATERIALS: From 2001 through 2006, 26 consecutive patients were treated on the trial. The primary objective was to demonstrate a high rate of completion without experiencing a treatment-limiting toxicity. Eligibility was limited to patients with T stage ≤ 2b, prostate-specific antigen (PSA) ≤ 20, and Gleason score ≤ 7. Treatment began with a single HDR fraction of 6Gy to the entire prostate and 9Gy to the peripheral zone, followed by IMRT optimized to deliver in 28 fractions with a normalized total dose of 70Gy. Patients received 50.4Gy to the pelvic lymph node. The prostate dose (IMRT and HDR) resulted in an average biologic equivalent dose >128Gy (α/β=3). Patients whose pretreatment PSA was ≥10ng/mL, Gleason score 7, or stage ≥T2b received short-term androgen ablation.
RESULTS: Median followup was 53 months (9-68 months). There were no biochemical failures by either the American Society of Therapeutic Radiology and Oncology or the Phoenix definitions. The median nadir PSA was 0.32ng/mL. All the 26 patients completed the treatment as prescribed. The rate of Grade 3 late genitourinary toxicity was 3.8% consisting of a urethral stricture. There was no other Grade 3 or 4 genitourinary or gastrointestinal toxicities.
CONCLUSIONS: Single-fraction HDR-boosted IMRT is a safe effective method of dose escalation for localized prostate cancer.
Written by:
Myers MA, Hagan MP, Todor D, Gilbert L, Mukhopadhyay N, Randolf J, Heimiller J, Anscher MS. Are you the author?
Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA.
Reference: Brachytherapy. 2012 Mar 30. Epub ahead of print.
doi: 10.1016/j.brachy.2011.07.006
PubMed Abstract
PMID: 22464911
UroToday.com Prostate Cancer Section