Primary epithelial-myoepithelial carcinoma of the lung with cavitary lesion: A case report.

Epithelial-myoepithelial carcinoma (EMC) typically arises in the salivary glands, whereas EMC of the lung is an extremely rare histological form that originates from the bronchial glands. Although cavitation in primary lung cancer is not uncommon, to the best of our knowledge, a case of EMC with a cavitary lesion has not been reported to date. We herein describe a case of cavity-forming pulmonary EMC. A 72-year-old man was referred to our department due to a thickened cystic wall discovered in the upper lobe of the left lung and underwent thoracoscopic left upper lobectomy. Microscopically, the tumor was characterized by biphasic architecture, with glands surrounded by myoepithelial cells. The pathological diagnosis was EMC. The patient has remained in good health for 2 years postoperatively, without any evidence of recurrence. As regards the mechanism of cavity formation, it was hypothesized that the bronchial gland in the primary cystic lesion had been present 3 years prior to the development of the EMC, and grew to become a cavitary lesion. Therefore, although the mechanism of cavity formation remains to be elucidated, EMC of the lung may include a cavitary lesion.