Bronchial adenoma--benign or malignant?

Bronchial adenomas grow slowly and are potentially malignant. Of the 45 cases reviewed, 36 were carcinoids, six were adenocystic carcinomas, two were mixed tumors, and one was mucoepidermoid carcinoma. The carcinoid group is subdivided into histologically typical 27(75%), atypical 9 (25%), and metastasizing 9 (25%) adenomas. There were 32 lobectomies, seven pneumonectomies, one sleeve resection, and two tracheal resections for adenocystic carcinoma. Ten-year survival rate was 88% for typical carcinoids, 66% for atypical carcinoids, and 44% for metastasizing carcinoids. In the cylindroma group, one patient was lost to follow-up, one died postoperatively, and one developed recurrence of the tumor eight years later. The only patient with mucoepidermoid carcinoma is alive without evidence of recurrence nine years after operation.