A Phase II Study Evaluating Bone Marrow-Sparing, Image-guided Pelvic Intensity-Modulated Radiotherapy (IMRT) With Cesium-131 Brachytherapy Boost, Adjuvant Chemotherapy, and Long-Term Hormonal Ablation in Patients With High Risk, Nonmetastatic Prostate Cancer

Purpose/Objective(s): Management of localized high-risk prostate cancer remains challenging. At our institution we performed a prospective phase II study of 2 years of androgen deprivation therapy (ADT), pelvic radiation, Cesium (Cs)-131 brachytherapy boost, and adjuvant docetaxel in high risk, localized prostate cancer with a primary endpoint of 3-year disease-free survival. Materials/Methods: Acute/chronic hematologic, gastrointestinal (GI) and genitourinary (GU) toxicities were scored based on the CTCAE v3.0/RTOG-EORTC criteria, respectively. Actuarial biochemical recurrence free survival (bRFS), bRFSdisease free survival (DFS) and overall survival (OS) were calculated. Patients had a median age of 62 years (range, 45 to 82), median Gleason score 8 (74% Gleason 8-10), median PSA of 11.2 (range, 2.8 to 96), and 47% cT2-T3a stage disease. Androgen deprivation was given for 2 years, 45 Gy whole-pelvis IMRT was followed by an 85 Gy Cs-131 boost to the prostate gland, and adjuvant docetaxel was given for 4 cycles. Results: In total 38 patients enrolled from 2006 to 2014, with 82% completing protocol specified treatment, and 84.2% completing 4 cycles of docetaxel. Median follow-up for the entire and alive cohorts were 44 months and 58 months (range, 3.4 to 118), respectively. Acute grade ≥2 GI and GU toxicity rates were 18.4% and 23.7%, respectively. Chronic grade ≥2 GI and GU toxicity rates were 2.6% and 2.6%, respectively. Twelve patients (31.6%) developed grade 4 hematologic toxicity, with no grade 5 toxicity. The 5-year DFS, bRFS and OS rates were 74.1%, 86.0%, and 80.3%, respectively. Conclusions: This aggressive pilot multimodal approach appears to be safe and well-tolerated, providing disease control in a significant proportion of patients with particularly high-risk prostate cancer. (1) Part of A.H.'s time was supported by a Merit Review Award (I01 BX000545), Medical Research Service, Department of Veterans Affairs. (2) Partly funded by Isoray (Richland, WA) which had no role in the design, conduct, review or analysis of data, nor in the preparation, approval or submission of the manuscript. The remaining authors declare no conflicts of interest. Reprints: Young Kwok, MD, Department of Radiation Oncology, University of Maryland Medical Center, 22 S. Greene Street, Baltimore, MD 21201. E-mail: ykwok@umm.edu. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

http://bit.ly/2T5KYsV