Drug may prevent the progression of high-grade PIN to prostate cancer

When prostate cells that line tiny sacs in the prostate and the ducts that carry fluid to the ejaculatory duct begin to look abnormal, pathologists render a diagnosis of prostatic intraepithelial neoplasia (PIN), classifying it as either high-grade or low-grade PIN. In high-grade PIN, the degree of cellular abnormality is more pronounced than in low-grade PIN, and studies have shown that high-grade PIN is more likely to progress to cancer.

In men with both prostate cancer and high-grade PIN, hormone therapy has markedly decreased the prevalence and extent of PIN. That got two Chinese researchers wondering: could a drug used for hormone therapy prevent the progression of high-grade PIN to cancer?

To find out, they followed 172 patients diagnosed with high-grade PIN but no evidence of prostate cancer for five years. Half took a small daily dose of flutamide for 12 months; the rest took a placebo. At the end of the study, 11.6% of the patients taking flutamide had developed prostate cancer compared with 30.2% of those taking a placebo, suggesting that a preventive dose of flutamide can keep high-grade PIN in check.

SOURCE: Zhao Z, Shen W. Flutamide Reduced Prostate Cancer Development and Prostate Stem Cell Antigen mRNA Expression in High-Grade Prostatic Intraepithelial Neoplasia. International Journal of Cancer 2007;122:864–70. PMID: 17957793.