Barrett’s esophagus is a precancerous condition that developed in approximately 10% of patients who have gastroesophageal reflux disease (GERD). In Barrett’s esophagus, the normal cells that line the esophagus called squamous cells turn into a type of cell called specialized columnar cells with intestinal metaplasia or Barrett’s esophagus.
How is Barrett’s diagnosed?
The diagnosis of Barrett’s esophagus involves an endoscopy procedure to look at the lining of the esophagus and biopsies to examine samples of suspect tissue. To do an endoscopy, your doctor gently guide a long thin to tube called an endoscope through the mouth and into the esophagus. The endoscope contains a camera and light that allows the doctor to see the lining of the esophagus and to remove a small tissue sample call a biopsy. The biopsy will be examined by a pathologist to see whether the normal squamous cells have been replaced with Barrett’s cells.
What is the risk of developing esophageal cancer?
Once the cells in the lining of the esophagus have turned into Barrett’s cells they will not revert back to normal. In about 5% of patients, the Barrett’s cells may develop abnormal changes called dysplasia. Over several years, the dysplasia may progress into adenocarcinoma (cancer) of esophagus. Patients with Barrett’s esophagus are 30-40 times more likely to develop esophageal cancer than the normal population.
There are different grades of dysplasia. Most patients will not develop any dysplasia within their Barrett’s esophagus. If minor concerning changes are noted by the pathologist under the microscope, the diagnosis of low-grade dysplasia is made. If major concerning changes occur, the diagnosis of high-grade dysplasia is made. High-grade dysplasia is very similar to carcinoma in situ or superficial cancer. While high-grade dysplasia has a high change of progressing into cancer, carcinoma in situ will eventually developing to invasive esophageal cancer if not treated.
Patients with Barrett’s esophagus are at higher risk than the general population for developing esophageal cancer. The standard of care for Barrett’s patients has been endoscopic biopsy surveillance to detect dysplasia or early cancer.
A question that is frequently asked is, why does one patient with Barrett’s esophagus progress to cancer while another patient does not? The answer is felt to lie in the genes of the esophagus that can change over time predisposing one to further genetic changes and eventually into cancer. By finding these abnormal genes early on, we may be able to intervene prior to the onset of dysplasia or cancer, thus preventing its development.
Most tests rely on a molecular biology technique of endoscopic biopsy samples. Extensive research is presently occurring to help find the right gene or set of genes that will predict with a high degree of certainly who will develop dysplasia and who will not.