Abstract
A case is reported of a 34 year old white male with chronic renal failure secondary to glomerulonephritis who received four renal transplants over a period of five years. He died 25 months after the fourth transplant. Necropsy revealed a reticulum cell sarcoma-microglioma of the brain. The possibility that multiple transplants may have had a synergistic effect in the development of a malignant cerebral lymphoma in this patient is briefly discussed in the light of the current theories concerning the pathogenesis of the tumours in transplant recipients and in the context of the present therapeutic approach to graft rejection.