Abstract: Objective: To investigate the CT and bronchoscopic characteristics of primary tracheobronchial adenoid cystic carcinoma, and to analyze the cellular morphologic features and diagnostic accuracy. Methods: A retrospective analysis was performed with 56 patients finally diagnosed primary tracheobronchial adenoid cystic carcinoma. All patients accepted chest CT scan and interventional bronchoscopy under general anesthesia．All patients were sampled for ROSE and pathological analysis. Results: Based on CT scan, the lesions of 56 patients located in trachea、main bronchus and segmental bronchus, were Abstract:Objective To investigate chest computerized tomography (CT) and bronchoscopic characteristics of primary
tracheobronchial adenoid cystic carcinoma (ACC), and to analyze the cellular morphologic features of rapid on-site
evaluation (ROSE) and diagnostic accuracy. Methods A retrospective analysis was performed with 56 patients diagnosed
as primary tracheobronchial adenoid cystic carcinoma. All patients accepted chest CT scan and interventional bronchoscopy
under general anesthesia．All patients were sampled for ROSE and pathological analysis. Results Based on CT scan, the
lesions located in trachea, main bronchus and segmental bronchus in 56 patients. The lesions were classified into localized
(28/56) and diffused (28/56) types. According to growing patterns, the lesions could be divided into three types: broadly basal
intraluminal nodules or masses (30/56), thickening type with infiltration along the wall (18/56) and intraluminal and outside
growing pattern (8/56). Bronchoscopic findings showed that eccentric constriction of the local lumens because of endoluminal
growth of ACC (67.86%) and circumferential stenosis because of diffuse thickness of mucosa (32.14%). The surface of the
lesion was smooth, but the surface blood vessels were abundant. ROSE showed that there were characteristic pink staining
spheric matrix and purple blue staining tumor cells at the same time. The diagnostic accuracy of ROSE was 92.9% (52/56).
Conclusion The CT and bronchoscopic features of primary tracheobronchial adenoid cystic carcinoma are characteristic,
and the accuracy of ROSE is high, which can be used as the basis for preliminary diagnosis.

Key words: trachea, adenoid cystic carcinoma, bronchoscopy, rapid on-site evaluation