A case of lymphoepithelioma-like carcinoma arising from the palatine tonsil.

Lymphoepithelioma is the designation that has been given to describe undifferentiated squamous cell carcinoma variants of nasopharyngeal neoplasms (World Health Organization type 3), and a strong association with Epstein-Barr virus (EBV) infection has been established. Outside the nasopharynx, lymphoepithelioma-like carcinomas (LEC) are exceedingly rare in other head and neck lesions. This report features a rare case of LEC of the palatine tonsil occurring in a 60-year-old Japanese man who presented with a three-month history of a neck mass. The surface of tonsils were smooth, not ulcerated macroscopically, and the ipsilateral tonsil showed only slight enlargement on radiological findings. Diagnosis of lymphoepithelioma was finally made based on the pathological review of the tonsillectomy specimens, preceded by a cervical lymph node biopsy. The patient was treated with irradiation and adjuvant chemotherapy. RNA in situ hybridization as well as polymerase chain reaction (PCR) techniques, and serological testing did not demonstrate an association with EBV infection. The clinical presentation, pathological features and association with EBV are described with a review of the literature.