The patient is a 61-year-old man who had previously undergone an extended thymectomy for myasthenia gravis. Endoscopic examination during a routine follow-up visit revealed early gastric cancer in the proximal portion of the stomach. To undergo resection the patient received general and epidural anesthesia. The conditions were unfavorable for laparoscopic-assisted surgery because he had a body mass index of 33 and muscle relaxants could not be used. Pneumoperitoneum was induced with carbon dioxide, and the abdominal wall was lifted. An adequate working space was secured in the upper abdomen and proximal gastrectomy was successfully performed.