A study suggests that drinking even a few glasses of alcohol per week increases the risk of breast cancer coming back (recurrence) in women who've been diagnosed with early-stage disease. These results were reported at the 2009 San Antonio Breast Cancer Symposium.
The results are similar to other studies suggesting that recurrence risk goes up if a woman drinks alcohol. Other research also has shown that the risk of being diagnosed with breast cancer is higher in women who drink alcohol.
Over a period of 8 years, researchers looked at the medical and alcohol consumption records of nearly 2,000 women diagnosed with early-stage breast cancer. About 350 women had a breast cancer recurrence and 332 women died during the 8 years. Not all the deaths were related to breast cancer.
Half of the women were characterized as moderate-to-heavy drinkers, meaning they had at least 3 or more drinks per week. Wine was the most popular alcoholic beverage, followed by liquor and beer.
The researchers looked at both the risk of recurrence and the risk of dying from breast cancer in women who were moderate-to-heavy drinkers compared to women who didn't drink alcohol.
- Women who drank 3 or more alcoholic drinks per week were 34% more likely to have a recurrence and 51% more likely to die from beast cancer compared to women who didn't drink.
- Postmenopausal women who drank alcohol had the largest increase in recurrence risk. Among moderate-to-heavy drinkers, recurrence risk was 51% higher in postmenopausal women and 24% higher in premenopausal women.
- Women who drank less than 3 alcoholic beverages per week had the same recurrence risk as women who didn't drink.
- The type of alcohol didn't seem to affect the amount of increase in recurrence risk among moderate-to-heavy drinkers.
- The risk of dying from causes other than breast cancer wasn't affected by how much alcohol the women drank.
Researchers don't completely understand why alcohol seems to increase the risk of breast cancer recurrence. Other studies have shown that hormone-receptor-positive breast cancer seems to be most affected by alcohol. Estrogen can cause hormone-receptor-positive breast cancer to grow and alcohol can increase the amount of estrogen in a woman's body. This increase in estrogen may be why there seems to be a link between drinking alcohol and breast cancer recurrence risk.
The bottom line is that we really don't know how much alcohol is safe for breast cancer survivors. If you've been diagnosed with early-stage breast cancer and want to do everything you can to lower your risk of recurrence, limiting how much alcohol you drink seems to make sense. You may even choose to stop drinking alcohol completely. It's also very important not to mix alcohol with some of the medicines you might be taking, such as pain medications.