SYMPOSIUM ON INTRATHORACIC NEOPLASMS .7. BRONCHIAL CARCINOID-TUMORS

Bronchial carcinoid tumors, termed (incorrectly) ''bronchial adenomas' ' in the past, are uncommon pulmonary neoplasms. These tumors are curr ently classified as neuroendocrine in origin because of their potentia l to form and sometimes secrete a variety of chemical substances. Over all, approximately 75% of bronchial carcinoid tumors arise in the loba r bronchi, 10% occur in the main-stem bronchi, and 15% originate in th e periphery of the lung. Well-differentiated carcinoid tumors constitu te almost 90% of all bronchial carcinoids. Atypical carcinoid tumors h ave a higher malignant potential than do typical bronchial carcinoids. The carcinoid syndrome is rarely, if ever, associated with carcinoids limited to the tracheobronchial tree. Occasionally, Cushing's syndrom e due to ectopic hormone production is caused by bronchial carcinoid t umors. More than 75% of bronchial carcinoids are detected on conventio nal posteroanterior chest roentgenograms. Computed tomography may help disclose small neoplasms that are occult on conventional roentgenogra phy, particularly in the assessment of patients who have Cushing's syn drome due to ectopic hormone production. Pulmonary resection is the tr eatment of choice for bronchial carcinoids. The prognosis is related t o the pathologic grade and stage of the tumor.