A new study finds that women who consume alcoholic beverages on a daily basis may be putting themselves at higher risk of breast cancer if they have a close relative who has had breast cancer. A number of previous studies have linked daily alcohol consumption to a slightly higher risk of breast cancer, although many of the studies did not take into account other risk factors of study participants, such as a family history of breast cancer, genetic mutation of a breast cancer gene, etc. This latest study suggests that alcohol can further increase an already elevated risk of breast cancer.
To conduct the study, Dr. Thomas A. Sellers and his colleagues from the Mayo Clinic in Rochester, Minnesota analyzed data from 426 families, which included a total of 9,032 women who either had blood-relatives with breast cancer or who had married into families that had a history of breast cancer. Of these women, 558 had developed breast cancer. Each woman was asked about average alcohol consumption and other factors, such as the use of hormone replacement therapy.
The researchers found that the women’s risk of breast cancer was greater if they drank alcohol on a daily basis and had a first-degree blood relative with breast cancer (a first-degree relative is a mother, sister, or daughter as opposed to a second-degree relative such as a grandmother or aunt). The women who consumed alcohol daily and married into a family with a history of breast cancer were not at as high of risk of developing breast cancer themselves. This suggests that alcohol increases the risk of breast cancer in women who already have a genetic susceptibility for the disease, according to the researchers. No specific information about genetic mutations of breast cancer genes or other genetic information was assessed in the study.
On the same note, Dr. Sellers and his colleagues found that the women who did not consume alcohol on a daily basis were at lower risk of developing breast cancer even though they had a close relative with breast cancer. Second degree relatives of women who had breast cancer, such as granddaughters and nieces, were only at a slightly higher-than-average risk of developing breast cancer themselves if they drank alcohol.
The research, which was funded by the National Cancer Institute, is one of several studies that have examined the link between alcohol and breast cancer risk. For example, in a study published in the February 18, 1998 issue of the Journal of the American Medical Association, researchers found that consuming at least 10 grams of alcohol (0.75 to 1 drink) per day slightly increased the risk of developing breast cancer. Another study published in the May 2, 2001 issue of the Journal of the National Cancer Institute suggested that drinking an average of one alcoholic beverage per day could raise the risk of breast cancer in post-menopausal women.
However, research has also suggested that moderate alcohol consumption can decrease the risk of heart disease. Heart disease is currently the leading cause of death in post-menopausal women and claims more lives than breast cancer and all other cancers combined. Therefore, researchers often advise women to discuss the issue of moderate alcohol consumption with their physicians. However, the risk of heart disease is more likely to be reduced by changes to diet and exercise and other measures, such as taking medicines to treat high cholesterol, than by drinking alcohol in reasonable quantities.
To date, the general consensus on alcohol and breast cancer risk is that alcohol may slightly increase the risk of breast cancer. However, it is not an established risk factor for the disease. Other factors have been more strongly linked to breast cancer. These factors include:
- Family or personal history of breast cancer
- Genetic mutations of breast cancer genes (BRCA1, BRCA2)
- Early menstruation (before age 12) or late menopause (after age 50)
- A history of pre-cancerous conditions such as lobular carcinoma in situ (LCIS) or atypical hyperplasia
Because the chances of successful treatment and survival are greater when breast cancer is detected in early stages, all women (including those with and without risk factors for breast cancer) should follow the American Cancer Society’s guidelines for early breast cancer detection:
- All women between 20 and 39 years of age should practice monthly breast self-exams and have physician performed clinical breast exams at least every three years.
- All women 40 years of age and older should have annual screening mammograms, practice monthly breast self-exams, and have yearly clinical breast exams. The clinical breast exam should be conducted close to and preferably before the scheduled mammogram.
- Younger women with a family or personal history of breast cancer should talk to their physicians about beginning annual mammograms before age 40.
- The study, "Investigation of an Interaction Of Alcohol Intake and Family History on Breast Cancer Risk in the Minnesota Breast Cancer Family Study," is published in the July 15, 2001 issue of Cancer. An abstract of the study is available at http://www3.interscience.wiley.com/cgi-bin/jtoc?ID=28741
- The May 29, 2001 Imaginis report, "Study Shows Moderate Alcohol Consumption May Increase Breast Cancer Risk," is available at http://www.imaginis.com/breasthealth/news/news5.29.01.asp
- The December 7, 1999 Imaginis report, "Daily Alcohol Consumption May Increase Breast Cancer Risk," is available at http://www.imaginis.com/breasthealth/news/news12.7.99.asp
- To learn more about risk factors for breast cancer, please visit http://www.imaginis.com/breasthealth/bc_risks.asp
