A common dementia in a rare disease.

The patient described was a 68-year-old man presenting with a severe, subacute depressive state with rapid decline in memory, psychomotor retardation and refusal to eat, who was referred by the medical team for ECT. His memory impairment could not be explained within the context of his depressed mood and he was eventually found to have a primary cerebral lymphoma of the non-Hodgkin's type. He died 10 weeks after initial psychiatric assessment.