Unusual presentation of lymphoepithelioma-like carcinoma of lung as a thin-walled cavity.

Most thin-walled cavities in the lung are benign lesions, but a few cases of lung cancer can have this unusual pattern. All previously reported cases were adenocarcinomas. Here we report a case of lymphoepithelioma-like carcinoma (LELC) of the lung presenting as a thin-walled cavity with a smooth inner surface. LELC is more commonly seen in Southeast Asia, including Taiwan, and its gross picture is usually a solid mass with a round, circumscribed border, which is indistinguishable from other non-small cell lung cancers. Asymmetric thickness of the cystic wall and lymphadenopathy are important features in the diagnosis and the selection of treatment.