NCI: A squamous cell carcinoma arising from the larynx. It is the most common type of laryngeal carcinoma. The site of origin within the larynx influences the symptoms, histologic characteristics, and clinical behavior of squamous cell carcinoma. The laryngeal squamous cell carcinomas can be glottic, supraglottic, and transglottic. Glottic carcinoma is the most frequent form of laryngeal carcinoma in the United States. Microscopically, squamous cell carcinomas of the larynx are similar in their appearance to squamous cell carcinomas arising elsewhere (adapted from Sternberg's Diagnostic Surgical Pathology, 3rd ed., 1999).