Bronchial adenoma--a heterogenous group of tumors: report of 38 patients.

Thirty-eight cases of bronchial adenoma seen at Taipei VGH during 1976-88 were reviewed. Nine were carcinoid tumors, 14 were mucoepidermoid carcinomas and 15 were cylindromas. There were 21 men and 17 women. Ages ranged from 6 to 81 years with a mean of 43. Twenty-five were primary tumors of lung and 13 were metastasized from distant sites. The commonest presenting symptoms were hemoptysis, persistent cough, dyspnea and chest pain. In primary bronchial adenomas, the mean duration of symptoms was similar for carcinoids and cylindromas, around 16 months, and shortest for mucoepidermoid carcinomas (2.9 months). Single mass lesion was the most common chest X-ray finding of primary adenomas, while multiple nodules were the commonest for metastatic adenomas. Most of the primary tumors (80%) were visible by bronchoscopy, which showed predilection of trachea for cylindromas, left-sided for mucoepidermoid carcinomas and right-sided for carcinoids. The mean age at presentation was similar for all types of primary adenoma, around 44.5 years, while more younger in patients with metastatic cylindroma than mucoepidermoid carcinoma. Most of the primary adenoma were resectable, however, post-operative chemotherapy or radiotherapy was required in 4 mucoepidermoid carcinomas and 2 cylindromas. All types of bronchial adenomas showed malignant potential, mean duration before metastasis was about 2 years (3 months to 4 years), most of them were mucoepidermoid carcinomas (60%). The 5-year survival rate was 11.1% for mucoepidermoid carcinomas, 55.6% for carcinoids and 83.3% for cylindromas. We conclude that the term bronchial adenoma represents a heterogenous group of tumors with considerable malignant potential and should not be ignored by its term of benignity.