Acid reflux disease may increase risk of cancers of the larynx and esophagus

GERD, a gastrointestinal disorder that affects approximately 20 percent of U.S. adults, occurs when stomach acid flows back into the esophagus, where it can cause tissue damage. Research indicates that this damage may put patients at risk of developing a type of cancer called esophageal adenocarcinoma.

To provide additional insights concerning this link and potential links to other types of cancer, a team led by Christian C. Abnet, PhD, of the National Cancer Institute, part of the National Institutes of Health (NIH), examined information on 490,605 adults enrolled in the NIH-AARP Diet and Health Study, a prospective study that mailed questionnaires in 1995-1996 to 3.5 million AARP members, aged between 50 and 71 years who were living in California, Florida, Louisiana, New Jersey, North Carolina, or Pennsylvania, or in the metropolitan areas of Atlanta, Georgia, and Detroit, Michigan.

Using Medicare claims data, the investigators estimated that 24 percent of participants had a history of GERD. Over the following 16 years after participants joined the study, 931 patients developed esophageal adenocarcinoma, 876 developed laryngeal squamous cell carcinoma, and 301 developed esophageal squamous cell carcinoma. People with GERD had about a two-times higher risk of developing each of these types of cancer, and the elevated risk was similar across groups categorized by sex, smoking status, and alcohol consumption. The investigators were able to replicate the results when they restricted analyses to the Medicare data subset of 107,258 adults.

The team estimated that approximately 17 percent of these cancers in the larynx and esophagus are associated with GERD.

"This study alone is not sufficient to result in specific actions by the public. Additional research is needed to replicate these findings and establish GERD as a risk factor for cancer and other diseases," said Dr. Abnet. "Future studies are needed to evaluate whether treatments aimed at GERD symptoms will alter the apparent risks."