Lymphoepithelioma‐Like Carcinoma of the Skin: A Case Report

Abstract

Lymphoepithelioma‐like carcinoma of the skin is a rare tumor with a microscopic resemblance to lymphoepitheliomatous carcinoma of the nasopharynx. We present a 93‐year‐old man with papules on the left auricle to the cheek that were gradually enlarged. By the time of a biopsy, it grew to a 5.0 × 3.0 × 2.8 cm dark red mass, and necrotic debris was attached to the surface. Histologically, a relatively well‐demarcated, dermal‐hypodermic multiple lobules were composed of irregular islands of atypical epithelial cells. The uniform tumor cells had moderate amounts of lightly eosinophilic cytoplasm and vesicular nuclei with one or two prominent nucleoli. A dense lymphocytic infiltrate was present within the neoplastic islands, obscuring the epithelial component. The neoplastic cells were unconnected to the overlying epidermis. Neither squamous nor glandular differentiation was present. Immunohistochemically, the neoplastic cells were positive for epithelial membrane antigen and cytokeratin, and negative for latent membrane protein 1. No Epstein‐Barr virus‐encoded RNA (EBER) was detected by in situ hybridization. The negativity for Epstein‐Barr virus may be a help in the differential diagnosis from metastatic undifferentiated nasopharyngeal carcinoma, which is uniformly positive for EBER.