Parameters for and safety of contact Nd:YAG laser irradiation of early gastric cancer: an in vitro study.

Early gastric cancers have been treated by endoscopic contact Nd:YAG laser irradiation. The extent of thermal damage produced by this laser system has been inadequately investigated. In an in vitro study we have shown that contact laser probes produce consistent and reproducible thermal lesions in the human stomach wall. Contact laser energies of 40 to 60 joules are optimal for the ablation of early gastric cancer. Energies greater than 90 joules are associated with a high incidence of gastric perforation. Contact laser probes may have advantages over non-contact laser techniques for the endoscopic treatment of early gastric cancer in patients who are unfit for major surgery.