PSA response to neoadjuvant androgen deprivation therapy is a strong independent predictor of survival in high-risk prostate cancer in the dose-escalated radiation therapy era

Int J Radiat Oncol Biol Phys. 2013 Jan 1;85(1):e39-46. doi: 10.1016/j.ijrobp.2012.08.036. Epub 2012 Oct 23.

Abstract

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.

Publication types

  • Evaluation Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • African Continental Ancestry Group
  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Androgen Antagonists / therapeutic use*
  • Disease-Free Survival
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Neoadjuvant Therapy / methods
  • Neoplasm Grading
  • Neoplasm Staging
  • Prostate-Specific Antigen / metabolism*
  • Prostatic Neoplasms / ethnology
  • Prostatic Neoplasms / metabolism*
  • Prostatic Neoplasms / mortality
  • Prostatic Neoplasms / pathology
  • Prostatic Neoplasms / therapy*
  • Radiotherapy Dosage
  • Survival Analysis
  • Time Factors

Substances

  • Androgen Antagonists
  • Prostate-Specific Antigen