Hepatic methotrexate-associated lymphoproliferative disease: a case report and literature review.

Background: Methotrexate-associated lymphoproliferative disease (MTX–LPD) is a rare and life-threatening complication of MTX administration. MTX–LPD features more extranodal lesions than malignant lymphoma; however, the liver is an extremely rare organ that develops LPD. Herein, we present a case of hepatic MTX–LPD treated with surgical resection. We also reviewed the literature on hepatic MTX–LPD. Case presentation: A 66-year-old man with a history of rheumatoid arthritis (RA) was admitted to our department for the treatment of hepatic solitary liver tumor. The patient had been receiving MTX (14 mg/week) for RA for 6 years. MTX was withdrawn and salazosulfapyridine was prescribed 3 weeks prior to admission because of mediastinal MTX–LPD. Abdominal contrast-enhanced computed tomography showed a slightly ring-like enhanced hypovascularized mass (80 mm) in the lateral section of the liver. Carbohydrate antigen 19-9 (78.1 U/mL) level was elevated. No evidence was observed on esophagogastroduodenoscopy or colonoscopy. The tumor was suspected to be an intrahepatic cholangiocarcinoma. The patient underwent hepatic lateral sectionectomy and lymphadenectomy. Pathological examination revealed that the hepatic mass was coagulative necrosis of the CD20-positive B-cell lymphocytes. These histological findings were similar to those of rapid necrotic lymphoma. MTX–LPD is known to spontaneously regress after withdrawing MTX, and the patient was diagnosed with hepatic MTX–LPD. Conclusions: MTX–LPD can occur in the liver. Clinician should suspect hepatic MTX–LPD when a liver mass is detected in patient who had been treating with MTX for RA. [ABSTRACT FROM AUTHOR]