CO2 laser in the diagnosis and treatment of early cancer of the vocal fold.

A total of 74 patients underwent cordectomy using CO2 laser for either diagnosis or treatment of an early cancer of the vocal fold. Type I cordectomy consisted in the resection of the entire epithelium, while leaving the vocal ligament intact. Type II cordectomy involved removal of the vocal fold from the vocal process to the anterior commissure and passing through the inferior thyroarytenoid muscle. Type IIIA required vocal fold resection along the internal side of the thyroid ala, while type IIIB included removal of the anterior commissure. Type I cordectomies were carried out with an Acuspot micromanipulator, which provided a 250-micron-diameter beam for a working distance of 400 mm, and in the shot-by-shot cutting mode with 3 W power superpulse. This cordectomy was carried out in 39 patients and a dysplasia or an early carcinoma were detected in 45.9% of cases. Type II and type III procedures were performed with the Microslad micromanipulator having a 700-micron-diameter beam in the continuous cutting mode, 7 W power superpulse. Fifteen cases were treated by type II cordectomy, of which 3 T1aN0M0 cases underwent postoperative radiotherapy due to insufficient resections and 2 cases with T1bN0M0 tumors later underwent reconstructive laryngectomy. A type III cordectomy was used for 14 cases of T1aN0M0 carcinomas and 3 cases of severe dysplasia. The margins of resection were found to be positive histologically in 23.5% of these cases, making frozen section examinations mandatory at time of surgery. Results of all procedures showed that voice was best after a type I cordectomy where only the epithelium was resected. In the type II and type III cordectomies, the quality of voice depended on the development of a fibrous fold and the absence of anterior synechia in the healed larynx.