Primary pulmonary lymphoepithelioma-like carcinoma initially diagnosed as squamous metaplasia: A case report and literature review.

A mass was detected in the middle lobe of the right lung of a 58-year-old female. The patient did not present any symptoms and was a nonsmoker. Diagnostic evaluation revealed squamous metaplasia in the middle lobe of the right lung. During surgery, a tumor was identified, which was diagnosed as a lymphoepithelioma-like carcinoma (LELC). LELCs have been mainly reported in the Asian population and are associated with the Epstein-Barr virus (EBVs), while they are not associated with smoking. Squamous metaplasia, which is the basis of squamous cell carcinoma, differs from LELC in the therapeutic methods used and the prognostic evaluation. Squamous metaplasia requires regular follow-up in out-patient clinics, while pulmonary LELC is treated by surgery and chemotherapy. Therefore, distinguishing between LELCs and other nonmalignant or premalignant conditions is essential.