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.
Originally published April 1, 2008; Last reviewed April 18, 2011