EPSTEIN-BARR VIRUS–POSITIVE MUCOCUTANEOUS ULCER IN A PATIENT PRESENTING WITH MONOCLONAL GAMMOPATHY

A 74-year-old man presenting with a gingival ulcer of 2 months’ duration was referred for evaluation. His medical history revealed a monoclonal gammopathy, which is under hematologic monitoring. At the first appointment, no lesion was observed. However, after 2 months an ulcerated and infiltrative lesion on the right lower posterior gingiva was present. Diagnostic hypotheses included lymphoma and squamous cell carcinoma. An incisional biopsy was performed and histopathologic evaluation showed ulceration of the mucosa with atypical lymphoid cells. Immunohistochemistry was positive for CD20, BCL6, MUM1, CD30, PAX5, and Epstein-Barr virus (EBV) markers. These findings, associated with the disease course, supported the diagnosis of EBV-positive mucocutaneous ulcer (EBV-MCU). Then, radiotherapy in a dose of 30 Gy was indicated. A complete clinical response was achieved and the patient is under follow-up with no recurrence. In conclusion, EBV-MCU should be considered as differential diagnosis for oral atypical ulcers.