The large number of people who drink beyond what is recommended for optimal health surprised researchers and raises questions about helping cancer survivors maintain their long-term health. “I think our study should serve as a beginning discussion point for future research. At the very least, our study suggests providers should ask about alcohol use and counsel patients engaged in heavy alcohol use to potentially cut down,” said the first author of the study, Nina Niu Sanford, MD, an assistant professor and Dedman Family Scholar in Clinical Care in the department of radiation and oncology at UT Southwestern Medical Center in Dallas. The study is the first large analysis on alcohol use in cancer survivors. RELATED: When Treatment Is Over: Actor Sterling K. Brown Puts a Spotlight on Life After Cancer

Drinking to Excess Relatively Common

The study assessed alcohol use in 34,080 people who reported a cancer diagnosis. The data was drawn from the National Health Interview Surveys from 2000 to 2017. Excessive drinking was defined as more than one drink a day in women and more than two drinks a day in men — the measure used by the U.S. Centers for Disease Control and Prevention (CDC). Typically binge drinking is defined as consuming enough alcohol to raise blood alcohol content (BAC) to at least the legal limit of 0.08 percent, according to the CDC. That usually means at least four drinks within two hours for women and at least five drinks for men. In the survey, however, binge drinking was defined as consuming at least five drinks in one day at any point over the past year. The study showed 56.5 percent of U.S. adult cancer survivors were current drinkers; 34.9 percent exceeded moderate drinking levels, and 21 percent engaged in binge drinking. Survivors who were between the ages of 18 and 34 and male were more likely to binge drink. Moreover, survivors of cancers diagnosed more commonly in younger people — such as cervical cancer, testicular cancer, head and neck cancers, and melanoma — were more likely to report drinking. Drinking was less common among survivors of breast cancer. While public health guidelines exist to help people avoid problems associated with drinking excessively, there are no studies that establish safe alcohol use levels in relation to cancer risk, Dr. Sanford said. RELATED: 5 Things Drinking Too Much Alcohol May Be Doing to Your Body

Alcohol and Cancer Risk: An Uncertain Connection

Heavy alcohol use is considered a risk factor for head and neck cancer, esophageal cancer, liver cancer, breast cancer, and colorectal cancer, according to the National Cancer Institute. Previous studies have suggested the more alcohol a person drinks regularly over time, the higher the risk of developing an alcohol-associated cancer. One study, published in the American Journal of Public Health, found an estimated 3.5 percent of cancer deaths in the United States are alcohol-related. But, Sanford said, “When it comes to more moderate and light drinking, the evidence is still split on how strong the association is.” The study also found that 16.7 percent of cancer survivors reported smoking. “Current or former smokers were more likely to use alcohol,” Sanford said. “Because we know for sure that smoking is a risk factor for cancer recurrence, making that association between drinking and smoking is important.” RELATED: Diet and Cancer: What You Need to Know — and Eat — to Feel Your Best While Fighting Cancer

Guidance on Alcohol and Smoking Needed for Cancer Survivors

The American Society of Clinical Oncology (ASCO) issued a statement in November 2017 in the Journal of Clinical Oncology identifying alcohol as a risk factor for some types of cancer and advocating improved patient, survivor, and physician education to reduce the risk. Current guidelines for the care of cancer survivors, including the NCCN Guidelines for survivorship, also recommend limiting the intake of alcohol. “But further work to understand optimal dissemination of these recommendations and ways to change alcohol use behavior is clearly needed in the cancer survivor population, particularly among younger survivors,” says Crystal S. Denlinger, MD, chief of GI medical oncology at Fox Chase Cancer Center in Philadelphia and chair of the NCCN Clinical Practice Guidelines in Oncology Panel for Survivorship. Dr. Denlinger was not involved in the study. Cancer survivors simply don’t understand the potential risks of alcohol consumption, says Sanford. “I think it’s our fault in some ways,” said Sanford. “These things aren’t discussed a lot with patients.” Until recently, the emphasis has been on surviving cancer. “But because our cure rate is improving, the focus has now, appropriately, shifted to cancer survivorship and maximizing quality of life and lifestyle and behavioral interventions,” said Sanford. RELATED: 7 Ways to Prevent Colon Cancer