TORONTO -- Stopping heavy drinking can significantly reduce the risk of esophageal and head-and-neck cancers, primarily squamous-cell carcinomas, researchers here said.
TORONTO, Sept. 27 -- Stopping heavy drinking can significantly reduce the risk of esophageal and head-and-neck cancers, primarily squamous-cell carcinomas, researchers here said.
In a pooled analysis of 13 studies, those who quit heavy drinking saw their risk of esophageal cancer and head and neck cancer return to normal after 20 years, according to Jrgen Rehm, Ph.D., of the Centre for Addiction and Mental Health and colleagues.
But the first few years after stopping saw a significant rise in development of both types of cancer, he and colleagues reported in the September issue of the International Journal of Cancer.
The researchers postulated that the increase immediately after quitting was the result of what they called the "sick quitter" effect, in which patients stop drinking because they are already suffering symptoms of cancer, although it had not yet been diagnosed.
But after five years in the case of esophageal cancer and 10 years for head and neck cancers, the risk begins to drop, Dr. Rehm and colleagues said.
"Alcohol cessation has very similar effects on risk for head and neck cancers as smoking cessation has on lung cancer. Dr. Rehm said. "It takes about two decades before the risk is back to the risk of those who were never drinkers or never smokers."
The finding comes from 13 case-control studies - five in esophageal cancer and eight in head and neck cancer - that included more than 5,000 cases, the researchers said. Most of the studies involved squamous-cell carcinoma.
Compared with current drinkers, people who have never used alcohol had a risk ratio for esophageal cancer of 0.37 and for head and neck cancers of0.46. Both risk reductions were significant at P
Nonetheless, they said, the study is comprehensive and provides the most accurate available odds ratios for alcohol cessation. "The risk reductions are quite large, especially for esophageal cancer," they said.