PURPOSE: The aim of the study was to evaluate the prognostic value of prostate-specific antigen (PSA) response to neoadjuvant androgen deprivation therapy (ADT) prior to dose-escalated radiation therapy (RT) and long-term ADT in high-risk prostate cancer.
METHODS AND MATERIALS: We reviewed the charts of all patients diagnosed with high-risk prostate cancer and treated with a combination of long-term ADT (median, 24 months) and dose-escalated (median, 75.6 Gy) RT between 1990 and 2007. The associations among patient, tumor, and treatment characteristics with biochemical response to neoadjuvant ADT and their effects on failure-free survival (FFS), time to distant metastasis (TDM), prostate cancer-specific mortality (PCSM) and overall survival (OS) were examined.
RESULTS: A total of 196 patients met criteria for inclusion. Median follow-up time for patients alive at last contact was 7.0 years (range, 0.5-18.1 years). Multivariate analysis identified the pre-RT PSA concentration (< 0.5 vs ≥0.5 ng/mL) as a significant independent predictor of FFS (P=.021), TDM (P=.009), PCSM (P=.039), and OS (P=.037). On multivariate analysis, pretreatment PSA (iPSA) and African-American race were significantly associated with failure to achieve a pre-RT PSA of < 0.5 ng/mL.
CONCLUSIONS: For high-risk prostate cancer patients treated with long-term ADT and dose-escalated RT, a pre-RT PSA level ≥0.5 ng/mL after neoadjuvant ADT predicts for worse survival measures. Both elevated iPSA and African-American race are associated with increased risk of having a pre-RT PSA level ≥0.5 ng/mL. These patients should be considered for clinical trials that test newer, more potent androgen-depleting therapies such as abiraterone and MDV3100 in combination with radiation.
Written by:
McGuire SE, Lee AK, Cerne JZ, Munsell MF, Levy LB, Kudchadker RJ, Choi SL, Nguyen QN, Hoffman KE, Pugh TJ, Frank SJ, Corn PG, Logothetis CJ, Kuban DA. Are you the author?
Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas.
Reference: Int J Radiat Oncol Biol Phys. 2012 Oct 23. pii: S0360-3016(12)03466-9.
doi: 10.1016/j.ijrobp.2012.08.036
PubMed Abstract
PMID: 23102837
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