Bronchial adenomas are a group of rare tumors representing less than 1 percent of primary lung neoplasms. Of 298 bronchial adenomas reported from the Mayo Clinic in 1978, 89 percent were classified as carcinoid tumors, 6 percent as adenoid cystic carcinomas, and 4 percent as mucoepidermoid carcinomas. Approximately 100 cases of primary mucoepidermoid carcinoma of the lung have been reported since this subtype was first recognized by Smetana et al in 1952. Histologically, this neoplasm is characterized by the coexistence of epidermoid, mucus-producing, and intermediate tumor cells. As a disease entity, it is distinctive for the infrequency with which it occurs, its variable clinical expression, and the occasional discordance between the tumors histologic grade and biologic behavior. In the majority of reported cases, the tumor has remained localized to the bronchus of origin, although extrabronchial spread occurs in approximately 25 percent of the patients. Exceedingly uncommon are reports of central nervous system involvement. Autopsy demonstration of metastases to the dura mater was documented by Dowling et al in one patient. Turnbull and coworkers also reported three patients with brain metastases. The following is, to our knowledge, the first roentgenographic and post-mortem description of a patient with mucoepidermoid carcinoma of the lung who presented with intracranial metastases. canadian family pharmacy
A 65-year-old man presented with complaints of drooling, progressive left facial drooping, and left arm weakness of one months duration. He denied visual disturbances, dysarthria, headaches or seizure activity His past medical history was significant for type II diabetes mellitus and diffuse atherosclerotic vascular disease. He experienced transient ischemic attacks, and had suffered two previous myocardial infarctions. He smoked two packages of cigarettes a day for 40 years.
The admitting physical examination revealed left central seventh cranial nerve palsy, decreased left arm strength and bilateral hyperreflexia. There was no lymphadenopathy. Results of the cardiac and pulmonary examinations were within normal limits.
Chest roentgenograms obtained eight months previously were normal except for left costophrenic angle blunting. The admitting chest roentgenograms demonstrated a left suprahilar mass and right hilar lymphadenopathy without any change in the left costophrenic angle blunting (Fig 1). Computed tomography (CT) of the thorax delineated aorto-pulmonic and circumferential paratracheal lymphadenopathy without a parenchymal mass lesion. Results of the head CT and bilateral carotid arteriography performed eight months earlier were normal except for diffuse atherosclerosis of the carotid arteries. The current head CT demonstrated a 2 cm ring lesion in the posterior right frontal lobe and a 5 mm ring lesion in the posterior left parietal lobe. Both of these lesions were associated with considerable edema and the right lateral ventricle was compressed.
To confirm the clinical suspicion of metastatic lung carcinoma, fiberoptic bronchoscopy was performed, but no endobronchial abnormality was found. Cytologic studies of bronchoscopic washing and brushing specimens, and subcarinal and left paratracheal transbronchial needle aspirates were negative for tumor cells. Two days later, the patient suffered a cardiopulmonary arrest and could not be resuscitated. An autopsy was performed.
Figure 1. The P-A chest roentgenogram demonstrates new right hilar (small arrow) and left suprahilar lymphadenopathy (large arrow), without change in the left costophrenic angle blunting noted eight months earlier.