Unilateral hyperlucency with left lower lobe mass in a patient with bronchial asthma.

Mucoepidermoid tumors are rare bronchial adenomas whose clinical presentation can mimic that of bronchial asthma. Bronchial adenoma should be included in the differential diagnosis of a patient with a persistent radiographic abnormality and clinical features of bronchial asthma. We present an adolescent female with a history suggestive of bronchial asthma and a persistent left lower lobe atelectasis, who later was found to have a low-grade mucoepidermoid tumor.