Revision 8 for 'Adenoid cystic carcinoma of the tracheobronchial tree'All Revisions
Adenoid cystic carcinoma of the tracheo bronchial tree
Adenoid cystic carcinomas (ACC's) of tracheo-bronchial tree are a type a low grade tracheal tumor. They are considered the second most common primary tumor of the trachea 3.
They are usually first recognized in patients in their 40s. There is no recognized gender predilection.
Symptoms in patients with adenoid cystic carcinoma are usually related to airway obstruction and therefore includes dyspnea, cough, stridor, wheezing, and hemoptysis.
The tumors may be histologically classified into tubular, cribriform, and solid subtypes 6.
The tumors are usually low grade but an occasionally undergo high grade tranformation 7.
Smoking does appear to affect the incidence.
Adenoid cystic carcinomas usually arise in the lower trachea . Less commonmy they are found in the mainstem bronchi, lobar bronchi and rarely, in the segmental bronchi and extrathoracic trachea.
On CT, these tumors have a notable tendency toward submucosal extension and typically manifests as either
- an intraluminal mass of soft-tissue attenuation with extension through the tracheal wall or
- diffuse or circumferential wall thickening of the trachea, a soft-tissue mass filling the airway or
- a homogeneous mass encircling the trachea with wall thickening in the transverse and longitudinal planes.
The longitudinal extent of the tumors are greater than their axial extent and the tumors usually involve more than 180° of the airway circumference.
They can be variable in shape rangin from polypoid to broad-based. Their margins are also variable and ranges from smooth to lobulated to irregular. Intratumoral calcification is rare.