Methotrexate-associated mantle-cell lymphoma in an elderly man with myasthenia gravis.

BACKGROUND

A 75-year-old man on methotrexate immunosuppression for myasthenia gravis presented with a 2-month history of lymphocytosis and bilateral inguinal adenopathy. There were no constitutional symptoms of fever, night sweats, or weight loss.

METHODS

Physical examination, blood tests, flow cytometry, fluorescent in situ hybridization, immunoglobulin gene sequencing, viral load quantification by real-time polymerase chain reaction, excisional lymph-node biopsy, bone-marrow biopsy, tumor morphology and immunohistochemistry, sequential CT and PET scans.

METHODS

Methotrexate-associated mantle-cell lymphoma.

RESULTS

Cessation of methotrexate, anthracycline-based combination chemo-immunotherapy, and maintenance rituximab.