Carcinoma of the subglottic area.

The subglottic area is defined as an anatomic region which is cylindrical in shape whose inferior margin is the inferior border of the cricoid cartilage and which is limited superiorly by an imaginary circle 5 mm below the free margin of the true vocal cords. Of 591 patients with glottic and subglottic cancers, only five (percent) had primary subglottic tumors and 132 (22 percent) had glottic tumors with subglottic extension. Sixty-five percent of the patients with glottic primary with subglottic extension were Stage 2 and 35 percent were Stage 3. Most patients were treated surgically. Hemilaryngectomy is a very satisfactory primary modality in the treatment of Stage 2 and some Stage 3 glottic lesions with subglottic extension. Stage 2 and 3 glottic cancers which involve greater than 10 mm of the subglottis carry a significantly decreased prognosis. Patients with T3 lesions with cord fixation with subglottic extension show a decreased survival.