Adjuvant radiation, androgen deprivation, and docetaxel for high-risk prostate cancer post-prostatectomy: Results of RTOG 0621.

Genitourinary (Prostate) Cancer
Session Type and Session Title: 
Poster Highlights Session, Genitourinary (Prostate) Cancer
Abstract Number: 
J Clin Oncol 32:5s, 2014 (suppl; abstr 5031)
Mark Hurwitz, A. Oliver Sartor, Qiang Zhang, Ying Xiao, Bobby Shayegan, Paul W. Sperduto, Kas Ray Badiozamani, Colleen Anne Lawton, Eric M. Horwitz, Jeff M. Michalski, Kevin S. Roof, David Beyer, Asha George, Howard Mark Sandler; Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA; Tulane University, New Orleans, LA; Statistical Center, Radiation Therapy Oncology Group, Philadelphia, PA; Thomas Jefferson University Hospital, Philadelphia, PA; Division of Urology, McMaster University, Hamilton, ON, Canada; Metro-MN CCOP, Waconia, MN; Virginia Mason Medical Center, Seattle, WA; Medical College of Wisconsin, Milwaukee, WI; Fox Chase Cancer Center, Philadelphia, PA; Washington University in St. Louis, St. Louis, MO; Southeast Radiation Oncology, Charlotte, NC; Arizona Oncology, Scottsdale, AZ; Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA

Abstracts that were granted an exception in accordance with ASCO's Conflict of Interest Policy are designated with a caret symbol (^).

Abstract Disclosures


Background: Phase III trials have shown benefit in progression-free survival and in some cases overall survival with adjuvant radiation therapy (ART) in men with adverse pathologic findings at radical prostatectomy (RP). Despite ART, a high-risk group of patients has been defined with 50% risk of progression at 3 years, a risk factor for prostate cancer specific mortality. RTOG 0621 is a single-arm phase II trial that assessed whether addition of androgen deprivation (ADT) and docetaxel to ART would increase freedom from progression (FFP) at 3 years from 50% to ≥ 70% in these high-risk patients. Methods: Eligible subjects had prostatic adenocarcinoma who underwent RP with PSA nadir > 0.2 and Gleason score ≥ 7 or PSA nadir ≤ 0.2 with Gleason score ≥ 8 and ≥ pT3. Subjects received 6 months of ADT + RT to the pelvis with prostatic fossa boost to 66.6 Gy followed in one month with 6 cycles of docetaxel 75 mg/m2 every 21 days. The primary objective was to assess whether addition of ADT and docetaxel to ART results in FFP of ≥70% as defined as PSA < 0.4 ng/ml, and no clinical failure or death from any cause at 3 years. Multivariate logistic regression was used to model association of factors with the occurrence of FFP. Odds ratios and respective 95% confidence intervals were computed. Results: 76 patients with median age 62 meeting eligibility criteria were enrolled on the study. 3 year FFP was 71%, (95% CI:61-81%), p-value<0.001. In univariate and multivariate models, only post-RP PSA was statistically significantly associated with FFP. Two deaths occurred of which only 1 was related to prostate cancer. The most common significant chemotherapy side effects were peripheral neuropathy (12 grade 2 and 1 grade 3) and febrile neutropenia in 3 patients. Six subjects (8%) experienced late grade 3-4 treatment related toxicities. Conclusions: Addition of ADT and docetaxel to ART for men as high risk of failure despite ART alone following prostatectomy resulted in a significant improvement in FFP as compared to historical controls. Phase III trials assessing chemotherapy in this high-risk population are warranted. This work was supported by RTOG grant U10 CA21661 and CCOP grant U10 CA37422 from the NCI and Sanofi-Aventis. Clinical trial information: NCT00528866.