Over the long-term, uncontrolled GERD can cause worrisome complications. One is esophagitis, an inflammation and erosion of the esophagus resulting from stomach-acid damage. Another is esophageal stricture, in which scar tissue causes the esophagus to narrow. In rare instances, a condition known as Barrett's esophagus, which is marked by changes to cells lining the lower esophagus, can lead to cancer.