Green Tea Extract may prevent the formation of mouth cancers in people with risk signs of the disease
According to the American Cancer Society, more than 35,720 are expected to be diagnosed with oral and/or pharyngeal cancer this year and the five year survival rate is less than 60%. Quitting tobacco and limiting alcohol intake sharply reduce any risk of oral cancer, even after many years of use. Leukoplakia is a white patch that can develop in the mouth. It is composed of abnormal cells and it can progress into oral cancer and up to about 25% of all cases of leukoplakia are premalignant.
In this new study over 50 per cent of participants in a University of Texas M. D. Anderson Cancer Center study experienced a clinical response to Green Tea Extract, according to findings published in the journal Cancer Prevention Research .
While still very early, and not definitive proof that green tea is an effective preventive agent, these results certainly encourage more study for patients at highest risk for oral cancer, lead researcher Vassiliki Papadimitrakopoulou, MD states. The extract's lack of toxicity is attractive - in prevention trials, it's very important to remember that these are otherwise healthy individuals and we need to ensure that agents studied produce no harm, he added.
The study is a phase II dose-finding trial. It followed 41 people with oral leukoplakia. The participants were assigned to receive either placebo or green tea extract three times a day. The researchers collected oral tissue biopsies, which they say was essential in that it allowed us to learn that not only did the Green Tea Extract appear to have benefit for some patients, but we pointed to anti-angiogenic (ability to kill off the abnormal cells) effects as a potential mechanism of action, explained co-researcher Anne Tsao, MD.
Almost 60 % of the people taking the two highest doses of the Green Tea Extracts had a clinical response. Just over 36 per cent of people in the lowest extract dose group had a clinical response, compared to 18 per cent in the placebo group said the researchers.
At an extended follow-up with a mean of 27.5 months, 15 participants had developed oral cancer, with a median time to disease development of 46.4 months. The study is published in the journal Cancer Prevention Research Volume 2, 931.