Previous reports have suggested that alcohol use helps cancers grow and now, new research offers a possible explanation for this phenomenon.

Rather than affecting the cancer directly, alcohol seems to work by promoting the growth of blood vessels that feed the tumor, according to a report in the medical journal Cancer.

The findings are based on tests conducted in chick embryos harboring human cancer cells. Some of the embryos were exposed to alcohol, while others were exposed to a mild saline solution.

Alcohol exposure for 9 days doubled the tumor size and the number of blood vessels compared with saline exposure, lead author Dr. Jian-Wei Gu and colleagues, from the University of Mississippi Medical Center in Jackson, note.

Further testing showed that alcohol increased the growth of blood vessel cells, but not tumor cells themselves, the researchers note.

“Although mounting epidemiologic evidence has indicated that alcoholic beverage consumption is a well-established risk factor for human (cancers), experimental studies have provided less than convincing evidence to support” this association, the investigators point out.

“To the best of our knowledge, this is the first report to show” in a living organism that alcohol increases tumor size and the number of blood vessels, they add.

SOURCE: Cancer, January 15, 2004.