HIF1A expression in localized prostate cancer treated with dose escalation radiation therapy.

Abstract

To analyze the expression of hypoxia inducible factor 1 alpha (HIF1A) and its correlation with clinical outcome in men with localized prostate cancer (PC) treated with dose escalation radiotherapy (RT) and androgen deprivation (AD). Between 1996 and 2004, 129 PC patients who had diagnostic biopsies pre-treatment and 24-36 months following RT were enrolled in this study. Median follow-up was 129 months. Suitable archival diagnostic tissue was obtained from 86 patients. Correlation analysis was done to assess association between HIF1A expression and clinical outcome. HIF1A expression was observed in 25/86 (29%) of diagnostic biopsies, and in 5/14 (36%) of post-RT biopsies. No significant association was noted between HIF1A expression and clinical and treatment parameters. We also failed to show a significant correlation between HIF1A overexpression and outcome. A borderline significant relationship was observed between expression of HIF1A and overall survival (OS) (HR 0.03, p=0.08). To our knowledge this is the first study assessing the pattern of change of HIF1A staining in biopsies of patients prior and following treatment. While we did not find significant variations in the expression of HIF1A following radio-hormone therapy, a high HIF1A expression was unexpectedly associated with a borderline improved OS.