The role of surgery in patients with Barrett's esophagus and high-grade dysplasia is controversial. The aims of this study were to determine the prevalence of unsuspected early cancer and to evaluate surgical outcome in a cohort of patients with high-grade dysplasia. Records of all 16 patients who underwent esophagectomy for high-grade dysplasia from 1986 to 1991 were reviewed. All had preoperative endoscopy with no gross evidence of carcinoma, and none had a preoperative diagnosis of intramucosal or invasive carcinoma. Intramucosal carcinoma was found in six (38%) resection specimens. There were no cases of invasive carcinoma or lymph node metastases. One patient (6%) died 3 months postoperatively. The remaining patients are alive without evidence of recurrent cancer (range of follow-up, 2-68 months). Early postoperative complications occurred in seven patients (44%). Late complications occurred in 11 patients (73%). Anastomotic strictures accounted for seven of the 11 (64%) late complications. Complications were successfully managed conservatively in all but two patients. One required laryngectomy for chronic aspiration and another required a gastrojejunostomy for gastric outlet obstruction. Intramucosal carcinoma that had been unsuspected is frequently found in patients with Barrett's esophagus and high-grade dysplasia. Mortality associated with esophagectomy is low, and perioperative complications can usually be managed conservatively. Esophageal resection is indicated in appropriately selected patients with Barrett's esophagus and high-grade dysplasia.