Association Between Acid Reflux and Oesophageal Cancer

Two new Mayo Clinic studies draw attention to the risk factors and possible genetic basis for Barrett’s esophagus and oesophageal cancer (adenocarcinoma). The studies were May 22-23, in Los Angeles at Digestive Disease Week 2006.

According to G. Richard Locke III, M.D., and Yvonne Romero, M.D., Mayo Clinic gastroenterologists and co-authors of one study, the incidence of esophageal cancer is increasing at what has been called an “epidemic” rate, but the cause for this increase is uncertain. Their team studied 186 cases of oesophageal and stomach cancer (adenocarcinoma) and found a significant association between oesophageal cancer and gastroesophageal reflux disease, also known as acid reflux. According to Dr. Locke, the research strengthens the understanding of the connection between acid reflux and oesophageal cancer. “But only about 5 percent of individuals who experience acid reflux will develop Barrett’s oesophagus,” says Dr. Romero. “And once Barrett’s oesophagus is diagnosed, patients have a 30- to 125-fold increased risk of developing oesophageal cancer.” Barrett’s oesophagus is a condition that occurs when acid reflux stimulates changes in the lining of the oesophagus so that it resembles the lining of the intestines. Currently, the only way to identify Barrett’s oesophagus is by performing an endoscopy. “Acid reflux is such a common problem that it is unrealistic to perform an endoscopic examination on everyone who experiences it,” explains Dr. Locke. “Thus, in order to learn what’s causing this increase in oesophageal cancer, we first need to know what’s causing Barrett’s oesophagus and whether there are any genetic risks for which acid reflux patients could be screened.” A second study, led by Dr. Romero, examined that question. Her team discovered strong evidence for susceptibility genes in familial Barrett’s oesophagus and oesophageal cancer (adenocarcinoma). The genetic linkage analysis was performed on 278 people in 31 families with two or more members affected by Barrett’s oesophagus, with or without oesophageal cancer. “Our research found areas on a chromosome that appear to be important for Barrett’s oesophagus and oesophageal cancer – so we’re on the right path,” says Dr. Romero. “Our next step is to look at 94 additional families to identify the particular genes associated with these disorders. Eventually, we’d like to develop a blood test for Barrett’s oesophagus to identify who has this precancerous lining early in their disease course, to ultimately prevent it from escalating into oesophageal cancer.” (Source: Mayo Clinic: May 2006.)