Squamous mucosa is the term for the inner lining of the esophagus. It is composed of flat squamous cells similar to those that make up the body's external skin, says The Society of Thoracic Surgeons.
Sometimes cube-shaped columnar cells replace the flat squamous cells of the esophageal lining, possibly as a healing response to damaged squamous mucosa, explains The Society of Thoracic Surgeons. The change to the mucosa results in a condition known as Barrett's esophagus, which leaves an individual with an estimated 40 times higher chance of developing esophageal cancer, though the absolute risk remains low. Barrett's esophagus is characterized as a complication of gastroesophageal reflux disorder, commonly known as GERD, notes the American Society for Gastrointestinal Endoscopy.
Treatment for GERD may help prevent Barrett's esophagus, thus lowering the risk for cancer, says Healthline. No recognized treatments exist to reverse Barrett's esophagus and the elevated risk it brings, says the American Society for Gastrointestinal Endoscopy, making prevention particularly important. ASGE describes experimental treatments that destroy the abnormal mucosa but carry their own risk of complications, and they have not yet proved to prevent cancer, as of 2015.
Individuals with diagnosed Barrett's esophagus should have an endoscopy and biopsy approximately every three years to check for precancerous changes, according to ASGE. The risk of esophageal cancer in Barrett's patients is still low, at about 1 in 200 per year.