Nivolumab for Methotrexate-associated Classic Hodgkin's Lymphoma in a Rheumatoid Arthritis Patient.

Nivolumab exerts therapeutic activity in patients with classic Hodgkin's lymphoma (CHL) but may cause several types of immune-related adverse events. Some rheumatoid arthritis (RA) patients develop CHL during methotrexate therapy (MTX-CHL); however, the efficacy and safety of nivolumab for these patients remain unclear. A 68-year-old woman was diagnosed with CHL after six years of MTX therapy for RA. The disease did not respond to any type of chemotherapy. Nivolumab was then initiated, and the patient was successfully treated without the reactivation of RA. The reactivation of RA always needs to be considered with the administration of nivolumab.