Methotrexate-associated lymphoproliferative disorder (MTX-LPD) involves lymphoid proliferations or lymphomas in subjects with autoimmune disease, especially rheumatoid arthritis (RA) treated with methotrexate (MTX). The relationship of MTX medication and LPD development has been discussed, and we report four cases of MTX-LPD.
Case 1: A 54-year-old woman administered MTX for RA since April 2007 was seen for right cheek and submandibular swelling in August 2008. Magnetic resonance imaging (MRI) showed cervical lymphadenopathy, necessitating lymph node biopsy revealing diffuse large B-cell lymphoma. MTX was discontinued and lymph nodes shrank within a month. In May 2009, general lymphadenopathy relapsed and she underwent chemotherapy.
Case 2: A 63-year-old man administered MTX for RA since June 1999 was seen for 1-year right submandibular swelling in January 2009. MRI showed submandibular lymph node swelling, necessitating lymph node removal yielding a pathological diagnosis of MTX-LPD similar to nodular lymphocyte predominant Hodgkin lymphoma. MTX was discontinued and the man has shown no sign of recurrence.
MTX-LPD incidence is expected to increase as MTX is used increasingly to treat RA. We should therefore take MTX-LPD in consideration when examining subjects treated with MTX.
