Primary central nervous system lymphoma mimicking recurrent depressive disorder: A case report

Primary central nervous system lymphoma (PCNSL) is a rare subtype of extranodal non-Hodgkin lymphoma, which is limited to the central nervous system. Few studies are available reporting psychiatric symptoms as the initial and dominant presentation of PCNSL. The current study reports the case of a PCNSL patient with a history of major depressive disorder and coexisting rheumatoid arthritis (treated with methotrexate), who initially presented with recurrent depressive disorder that showed no response to antidepressant drug therapy. Magnetic resonance imaging revealed multiple mass lesions in the brain, and pathological examination of the biopsy confirmed the diagnosis of diffuse large B cell lymphoma of the central nervous system. The present case demonstrated that PCNSL may affect mood in the early stages of the disease and thus, clinicians must be aware of this manifestation in patients with depressive disorder co-existing with immunosuppressive conditions, as early detection and appropriate treatment are important prognostic factors for PCNSL.