We report the use of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser ablation to treat high-grade dysplasia and intramucosal esophageal adenocarcinoma associated with Barrett's esophagus in a patient who refused surgery. Throughout laser therapy, the patient received omeprazole 40 mg/day. After 1 1/2 yr, five laser treatments totaling 22,055 J given over a period of 13 months achieved squamous reepithelialization and absence of malignant transformation in the first area in which carcinoma was diagnosed. Squamous reepithelialization was maintained 1 yr later, confirming recent reports that photoablation plus omeprazole can achieve regression of Barrett's esophagus. During the last year of follow-up, a second contiguous area discovered to contain carcinoma was treated three times by photoablation, with a total of 13,164 J; biopsy showed only low-grade dysplasia in this area after two laser treatments totaling 8,108 J. No complications were seen during or after any of the laser sessions, and the patient remained asymptomatic 2 1/2 yr after the first photoablation and 3 yr after presentation.