A recent Kaiser Permanente study may help oncologists answer one of the most common questions they get from breast cancer survivors: Is it safe for me to drink alcohol?

The study suggests drinking alcohol is not associated with an increased risk of having a breast cancer recurrence or dying from the disease.

“We know that women who drink alcohol are at higher risk of developing breast cancer and that the risk increases as alcohol use increases,” said lead author Marilyn Kwan, PhD, a research scientist with the Kaiser Permanente Northern California Division of Research. “For this reason, we thought that drinking alcohol after a breast cancer diagnosis could increase the risk of a cancer recurrence. But our study found that, overall, drinking alcohol after a breast cancer diagnosis does not impact a patient’s prognosis.”

The research team used data from the Pathways Study, a long-term study following 4,504 women diagnosed with breast cancer from 2005 to 2013 at Kaiser Permanente Northern California. It is one of the largest U.S. studies to follow breast cancer survivors to learn more about the relationship between lifestyle changes and outcomes.

“After a breast cancer diagnosis, patients are often focused on making lifestyle changes that could help them live longer,” said senior author Lawrence H. Kushi, ScD, a research scientist at the Division of Research who co-leads the Pathways Study. “The aim of our study is to provide breast cancer survivors and their physicians with information that can help them make decisions that will improve both their quantity and quality of life.”

“Our Kaiser Permanente survivorship clinicians will now be empowered with data from our own health system to provide better evidence-based counseling to their patients with breast cancer.”   

Raymond Liu, MD

The study, published in Cancer in August, included 3,659 women who had completed questionnaires about their alcohol use at the time of their breast cancer diagnosis and again 6 months later.

Over the next 11 years, 524 women had a breast cancer recurrence and 834 women died — 369 from breast cancer, 314 from cardiovascular disease, and 151 from other health problems. The researchers determined that, overall, there was no association between drinking alcohol and risk of recurrence or death.

Previous studies that have looked at associations between alcohol use and breast cancer risk have had conflicting results. And most were focused on alcohol use before breast cancer. As a result, there are currently no guidelines for breast cancer survivors on alcohol use. Guidelines for preventing breast cancer recommend that women have no more than one alcoholic drink per day.

“This study is directly applicable to the thousands of women who survive breast cancer each year, as alcohol use is one of the most common lifestyle questions in breast cancer survivorship,” said Raymond Liu, MD, an adjunct investigator with the Division of Research and the director of cancer survivorship for Kaiser Permanente in San Francisco. “Our Kaiser Permanente survivorship clinicians will now be empowered with data from our own health system to provide better evidence-based counseling to their patients with breast cancer.”

400