Doctors can sometimes see the cancer coming years earlier when acid reflux causes cells in the esophagus to mutate to become more like stomach tissue, a condition called Barrett's esophagus.

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This comes from the work of Carlo Maley and his colleagues working on Barrett's Esophagus.

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Another side effect of chronic heartburn is a condition known as Barrett's esophagus, which happens when there's a change in the cells of the tissue lining the bottom of the esophagus.

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