Mucoepidermoid carcinoma of the bronchus presenting with a negative chest X-ray and normal pulmonary function in two teenagers: two case reports and review of the literature.

Two adolescents presented with a history of dyspnea upon exertion and cough. In both cases, the chest X-ray and pulmonary function testing, including flow-volume loop, were normal. A bronchial tumor was diagnosed by CT scan, which was ordered after each patient had an episode of hemoptysis. The sedimentation rate was the only abnormal laboratory test in both cases. Mucoepidermoid carcinoma of the bronchus, a rare tumor in childhood, was found at pathology in both cases. There was no evidence of metastases to local lymph nodes or distal sites. There were 47 previously reported cases in children. Recurrent pneumonia and persistent cough were the most common presenting findings. These tumors are of low-grade malignant potential but they can become locally invasive, extending into cartilage and surrounding soft tissue. Prognosis is good with complete resection.