A Case of Primary Myoepithelial Carcinoma of the Lung Resected Surgically

Abstract

A 67-year-old man presented with a nodular lesion in the lower lobe of the left lung. Computed tomography that was carried out as a screening for his elevated serum carcinoembryonic antigen (CEA) level detected a small nodule at the posterior basal segment (S¹⁰) of the left lung. The pulmonary nodule developed a tendency to enlarge in a half year. Because of a clinical suspicion of malignancy, he underwent a thoracoscopic wedge resection of the left lower lung. Histopathologically, the tumor was composed of atypical cells arranged in trabecular or alveolar pattern, and the tumor cells had clear cytoplasm. No ductal structures were found throughout the tumor. Immunohistochemical staining showed the tumor cells to be positive for 34βE12, S-100, α-SMA, and P-63. On the basis of the above features, the tumor was diagnosed as primary myoepithelial carcinoma of the lung. The patient is doing well without recurrence for 4 years and 9 months after the operation.