Low-grade Malignant Tumor of the Tracheobronchial Tree : Bronchoscopic Findings and Clinical Features

Abstract

We evaluated the bronchoscopic findings and the clinical courses of so-called low-grade malignant tumor which originated in major airway. These consisted of 10 cases of central type carcinoid, 5 adenoid cystic carcinomas and 3 mixed tumors. Endoscopical findings showed the polypoid type of carcinoid had a pale or red color, but did not find submucosal invasion. Adenoid cystic carcinoma occurred in major bronchi more frequently than the other tumors, and showed longitudinal and submucosal invasion with vascular engorgement. Three out of 5 patients had a poor outcome. In mixed tumor there were no typical bronchoscopic findings. Three cases of adenoid cystic carcinoma and 1 mixed tumor had stage III or IV invasive tumors, and all 4 died of primary cancer. The survival time of resectable cases veraged 60 months (6∿153months). The five year survival rates for the three types (carcinoid, adenoid cystic carcinoma and mixed tumor) were 67%, 30% and 67%, respectively. Therefore, the early diagnosis is important even for low-grade malignant tumors.