Fifty-four patients have been successfully endoscopically treated without complications using contact neodymium:YAG laser probes (endoprobes) for tumors and bleeding and, during open surgery (laser scalpel), for liver and pancreatic resections. The contact probes made from a synthetic sapphire crystal with its optical properties, geometric design, and thermal conductivity have proven to be more effective than the current conventional noncontact method of delivering laser energy through a quartz fiber. Advantages include greater precision, sterilizability, avoidance of the tip melting, and a requirement for lower neodymium:YAG laser energy with reduced tissue damage. The configuration of the probes allows coagulation, cutting, or vaporization, depending on the clinical condition being treated.