Barrett's esophagus and esophageal cancer.

Adenocarcinoma arising in Barrett's esophagus is increasing in incidence and accounts for a substantial portion of intrathoracic esophageal malignancies today. Patients with Barrett's esophagus have a 50 to 100 times increase in their risk of developing cancer compared to the general population. Malignant degeneration of the columnar epithelium appears to pass through a phase of dysplasia prior to the development of invasive malignancy. Low-grade dysplasia often remains stable or regresses. High-grade dysplasia, however, is considered equivalent to carcinoma in situ and is a predictor of imminent or existing invasive cancer. Endoscopic surveillance can detect malignant change at an early stage when it is likely to be curable by surgery. Patients undergoing endoscopic surveillance of Barrett's esophagus compared to those not under surveillance have a significantly improved postoperative survival owing to earlier detection.