Diagnostic Odyssey: Primary CNS Lymphoma (Lymphoma Cerebri) Presenting as Rapidly Progressive Dementia.

Primary central nervous system lymphoma (PCNSL) is a rare brain cancer that sometimes presented as rapidly progressive dementia. Diagnosing PCNSL presenting with rapidly progressive neurocognitive symptoms can be challenging, especially when the patient was previously treated with immunosuppressants for suspected autoimmune processes. We present a case where PCNLS was eventually and successfully treated 18 months after neurological symptoms started.