Flexible Nd:YAG laser palliation of obstructive tracheal metastatic malignancies. Flexible Nd:YAG endoscopic laser surgery may become an effective new modality for palliation in patients with obstructive endotracheal metastatic malignancies. We report the results of the treatment of two patients with severely obstructing intraluminal tracheal metastatic melanoma and medullary thyroid carcinoma, using the neodymium-YAG laser via the flexible fiberoptic bronchoscope. Both patients complained of significant dyspnea, orthopnea, cough, and hemoptysis and were not candidates for rigid bronchoscopy because of underlying medical contraindications and anatomical problems. Multiple treatment sessions were used with treatment intervals of 1 to 2 weeks. All treatments were performed in the operating room under sedation, without intubation, with topical lidocaine and standard superior laryngeal nerve block. Successful relief of airway obstruction with complete regression of the endotracheal masses was achieved and no recurrences were seen after 9 months' follow-up. Flexible Nd:YAG laser bronchoscopy offered an alternative for the relief of obstructing endotracheal or bronchial malignancies in patients in whom the rigid bronchoscope could not be passed. it seemed to prolong survival in selected cases, and provided definite improvement in quality of life. 