Pathology of Primary Tracheobronchial Malignancies Other than Adenoid Cystic Carcinomas.

Most primary tracheal tumors are malignant. Malignancy of larynx and bronchi are much more likely than trachea. Tracheal tumors are most likely due to direct extension for surrounding tumors. Squamous cell carcinoma and adenoid cystic carcinoma make up about two-thirds of adult primary tracheal tumors. Because of their predominantly local growth pattern, malignant salivary gland-type tumors show a better outcome than other histologic types.