For breast cancer survivors, regular consumption of alcohol may increase the risk for a recurrence of the disease, according to research presented this week at a conference of the American Association for Cancer Research in Houston. In a study of nearly 1,900 women who had initially been diagnosed with early stage breast cancer between 1997 and 2000, researchers found that those who had three to four drinks per week had a 30% higher risk of having a breast cancer recurrence compared with breast cancer survivors who did not drink.
The study, funded by the National Cancer Institute and led by Kaiser Permanente staff scientist Marilyn Kwan, followed participants for eight years, during which time there were 349 breast cancer recurrences and 332 deaths, from both cancer and other causes. Half of the study population were categorized as drinkers—meaning they consumed more than a fraction of an ounce of alcohol per day—and wine was the drink of choice for most. Of study participants who drank regularly, 90% drank wine, 43% drank hard alcohol, and 36% drank beer.
Cancer recurrence was most common among women who had already been through menopause, and among overweight or obese women. Researchers suggest that alcohol may increase the risk for breast cancer recurrence by increasing estrogen production, which in turn can drive tumor growth. The combination of alcohol consumption and obesity may work in concert to perpetuate this problem, they say, as obesity too can promote estrogen production by causing increases in sex hormones and insulin levels.
While wine was the most popular choice of alcoholic beverage among women in the study, researchers found no correlations between different types of alcohol and risks for cancer recurrence. Additionally, they found no associated risk between low levels of alcohol consumption—fewer than three drinks per week—and cancer recurrence in breast cancer survivors. And, while regular drinking (more than three or four drinks per week) was correlated with elevated risk for cancer recurrence, it was not linked to a higher risk of overall mortality.
So, what does this mean for breast cancer survivors? These are preliminary findings and further study is needed, but in the meantime, researchers say that for women who have been diagnosed with breast cancer—and especially those who are postmenopausal or overweight—it may be a good idea to talk to your doctor about cutting back on the Chianti.