Primary central nervous system lymphoma (PCNSL) is a high-grade malignant B-cell non-Hodgkin neoplasm that is an infrequent variant of all intracranial neoplasms (1%) and all lymphomas (< 1%)

PCNSL is documented mainly in immunocompromised patient groups, although it may also be diagnosed in immunocompetent patients. It affects mainly the eyes, supratentorial areas, or the spinal cord. The lesions are typically localized in frontal lobes, corpus callosum and basal ganglia. Additionally, lesions might rarely be detected at infratentorial areas and in medulla spinalis. Even though a wide spectrum of treatment options are available, such as chemotherapy, radiotherapy, or surgery; response rates are low and prognosis is poor in spite of appropriate treatment.

The case we reported here is 57-year-old male presented with symptoms of aggresivity, impulsivity, depressive mood and personality changes. Histopathological diagnosis was CD5 positive diffuse large B cell lymphoma, which is very rare in high-grade lymphomas. There were no neurological signs related to CNS tumor and the clinical manifestations responded very well to chemotherapy consisting of high dose methotrexate, vincristine and procarbazine. The significance of such neuropsychiatric symptoms in the course of treatment for PCNSL has been previously documented as well. These behavioral and emotional symptoms might manifest themselves based on where the neoplasm is localized. Therefore, psychiatrists should be more aware of the uncommon manifestation of the disorder as reported in this case. Consultation for differential diagnosis might also be necessary in such cases.