A case of EBV-positive mucocutaneous ulcer involving the maxillary gingiva

Abstract

An Epstein-Barr virus-positive mucocutaneous ulcer （EBVMCU） is a mature B-cell tumor that occurs in the oropharynx, skin, and digestive organs. Although EBVMCUs were established as a disease based on the WHO classification of hematopoietic tumors in 2017, reported EBVMCU cases in the oral cavity, including our case, are still rare. Herein we report a 79-year-old Japanese woman with a 1-month history of a painful mass involving the right side of the maxillary gingiva. The patient had rheumatoid arthritis and had been treated with methotrexate （MTX） for 11 years. Based on a pathologic evaluation of a biopsy specimen and the FDG PET-CT findings, an EBVMCU was diagnosed. Because an EBVMCU can be cured without chemotherapy, our patient had a spontaneous remission after withdrawal of MTX, without a recurrence in 18 months.