By Megan Rauscher

Compounds found in green tea may prevent the development of prostate cancer in men with a pre-cancerous condition called high-grade intraepithelial neoplasia (PIN), researchers have shown.

"The sad truth is that close to 30,000 men will die from prostate cancer in the United States every year and, at present, prevention is the best way to fight it, Dr. Saverio Bettuzzi from the University of Parma in Italy told Reuters Health. High-grade PIN progresses to invasive prostate cancer within a year in about 30 percent of men and no treatment is given to these men with high-grade PIN until prostate cancer is diagnosed. Green tea catechins (GTCs) may be the answer, Bettuzzi said at the gathering of the American Association for Cancer Research here.

The investigator performed a trial involving men with high-grade PIN, who were given an inactive placebo preparation or one containing 600 milligrams of GTCs daily, "equivalent to 12-15 cups of green tea infusion, that is about two times the average intake in Asian countries." Bettuzzi reported that, after a year, only 1 man among 32 in the GTC group developed prostate cancer, a rate of only 3 percent. In contrast, 9 out of 30 men treated with placebo developed prostate cancer, for the expected rate of 30 percent. "To our knowledge, this is the first study showing that GTCs have potent in vivo chemoprevention activity for human prostate cancer," Bettuzzi noted.

"The interest in GTCs and other polyphenols — antioxidants found in many plants — derives from traditional Chinese medicine, but the Mediterranean diet is very rich in vegetables, thus providing high levels of polyphenols, and lower rates of prostate cancer are found in that region as well," he pointed out. "There are other studies strongly suggesting that similar results could be obtained for prevention of other types of cancer. As a matter of fact, breast and colon cancer are possible targets. In the near future, we are supposed to start a collaborative trial involving both Italy and USA on this matter," Bettuzzi concluded.