Mucoepidermoid lung tumors.

Mucoepidermoid lung tumors are uncommon, representing 0.2% of all lung tumors and 1% to 5% of bronchial adenomas. Eighteen patients with mucoepidermoid tumors are reported. There were 10 male and 8 female patients with a mean age of 36.8 years (range, 9 to 62 years). On the basis of mitotic activity, cellular necrosis, and nuclear pleomorphism, we subclassified these tumors as low grade (15 patients) or high grade (3 patients). The achievement of complete resection and low-grade versus high-grade staging correlated with prognosis. All 12 patients who had a low-grade tumor that was completely excised are alive with no evidence of disease at a mean follow-up of 4.7 years (range, 1 to 27 years). All high-grade tumors proved fatal within 16 months. Two of the 3 high-grade tumors were unresectable because of extensive local disease. Patients with low-grade tumors and microscopically positive margins require close follow-up and can undergo a successful repeat resection. Nine of the 16 resections were sleeve resections, high-lighting the importance of conservative lung-sparing procedures in these central airway tumors. Both patients with an unresectable high-grade tumor had radiation therapy postoperatively and died 11 months later. The role of radiation therapy with high-grade tumors or incomplete resection has yet to be determined.