Malignant lymphoma of the upper gingiva considered as a methotrexate-associated lymphoproliferative disorder (MTX-LPD): Case Report

Abstract

We report a case of malignant lymphoma of the upper gingiva that was considered as a methotrexate-associated lymphoproliferative disorder (MTX-LPD). A 68-year-old woman was referred to our hospital with suspected cancer of the upper gingiva. She presented with an ulcer of the upper gingiva. Two biopsies under local anesthesia did not provide a definitive pathologic diagnosis. She was subsequently hospitalized with growing ulcer and pain. We performed biopsy under general anesthesia to achieve a definitive diagnosis. Histopathological examination of the biopsy specimens revealed diffuse large B-cell lymphoma. The patient had an 11-year history of rheumatoid arthritis (RA), and had been taking MTX for 8 years. Therefore methotrexate-associated lymphoproliferative disorder (MTX-LPD) was suspected and MTX therapy was discontinued.
The incidence of MTX-LPD may increase in otolaryngological practice because MTX therapy is the standard treatment for RA. The authors emphasize the importance of considering this disease if a patient with RA complains of a mass.