New York, Feb 22 : Acid reflux disease which also causes heartburn symptoms is linked with higher risks of various cancers of the larynx (or voice box) and esophagus, suggests new research. Gastroesophageal reflux disease (GERD) 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 Abnet of the National Cancer Institute, part of the US National Institutes of Health (NIH), examined information on 490,605 adults enrolled in the NIH-AARP Diet and Health Study. Using Medicare claims data, the investigators estimated that 24 per cent 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 categorised by sex, smoking status, and alcohol consumption, said the study published early online in CANCER, a peer-reviewed journal of the American Cancer Society. "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 Abnet. "Future studies are needed to evaluate whether treatments aimed at GERD symptoms will alter the apparent risks." /IANS