2016 Volume 62 Issue 2 Pages 57-62
The patient was a 63-year-old woman who had been diagnosed with rheumatoid arthritis over 40 years previously and had been taken methotrexate (MTX) and tacrolimus for 10 years. She visited an ENT clinic due to a left parotid mass and pain in August 201X. Parotid MRI revealed a tumor in the left parotid gland and fine needle aspiration cytology showed class Ⅲ b. According to these findings, we suspected a malignant parotid tumor and she was referred to our hospital for surgical resection. She underwent total parotidectomy due to suspicion of a malignant parotid tumor. The pathological diagnosis was diffuse large B-cell lymphoma (DLBCL) and the patient was positive for EBER. Therefore, the patient was diagnosed with methotrexate-associated lymphoproliferative disorder (MTX-LPD). After the diagnosis, MTX was discontinued and the patient has not exhibited disease relapse. MTX-LPD should be kept in mind for patients with rheumatoid arthritis treated with MTX.
