thumb<unk>  (TO) is a rare benign disease of unknown cause, in which multiple cartilaginous or bony submucosal nodules project into the trachea and proximal bronchi. The nodules usually spare the posterior wall of the airway because they are of cartilaginous origin, while the posterior wall of the airway is membranous (does not contain cartilage). This is as opposed to tracheobronchial amyloidosis, which does not spare the posterior wall. It usually occurs in men around their fifth decade of life, as opposed to tracheobronchial papillomatosis due to HPV infection, which usually occurs in younger patients. TO can cause airway obstruction, bleeding and chronic cough. Treatment involves the use of bronchodilators, and physical dilatation by bronchoscopy. The patients are also more prone to post-obstructive pneumonia and chronic lung infection in severe cases.
Tracheobronchopathia osteochondroplastica
Bronchogenic cyst
Pancoast tumor
Vocal cord cyst
Nasopharyngeal angiofibroma
Scalp–ear–nipple syndrome
Tracheoinnominate fistula
Bronchial leiomyoma