Endoscopic treatment of superficial gastric cancer has been reported to be effective by many Japanese teams. In this study, the Nd:YAG laser was used to treat superficial gastric carcinoma in inoperable Caucasian patients with the aim of obtaining a complete response, i.e., disappearance of the lesion endoscopically and biopsy specimens negative for cancer. Eighteen patients unsuitable for surgery with various endoscopic patterns of superficial gastric cancer were treated with the Nd:YAG laser. The endoscopic pattern was type I in 4 patients, type II in 10 (5 type IIa, 1 type IIb, 2 type IIc, 2 mixed IIa + IIc), and type III in 4. Staging by echoendoscopy was performed in 11 patients (T1N0). Nd:YAG laser destruction of the gastric tumor was performed in all cases, with a mean of 4.4 laser sessions per patient. Tumor response was assessed by endoscopy and biopsy. Follow-up averaged 33 +/- 23 (SD) months. Five patients died of diseases unrelated to gastric cancer. An initial complete response was obtained in 16 (89%) patients after a mean of 1.7 laser sessions; histologic evidence of cancer persisted in 2 patients during the entire follow-up period. Among patients with an initial complete response, recurrence was observed in 2. One of them was successfully re-treated. At the end of the follow-up period, 14 (77.7%) of the 18 patients had a complete tumoral response; only 4 patients had histologic evidence of cancer. In 3 of these 4 patients, pretherapeutic echoendoscopic staging had not been performed. Among the 14 patients exhibiting a complete response, 3 had negative biopsy results more than 5 years after diagnosis. No complications occurred. In gastric cancer classified as T1N0 on the basis of pretherapeutic echoendoscopy, a high tumor response rate and even 5-year disease-free survival can be obtained with endoscopic Nd:YAG laser treatment. Endoscopic laser destruction thus appears to be a valuable therapeutic alternative to surgery in inoperable patients with superficial gastric cancer.