Granulocytic sarcoma of the brain after renal transplantation

A case of granulocytic sarcoma of the brain in a renal transplant recipient treated with immunosuppressive agents is presented. While the increased risk of malignant lymphoma, particularly large-cell lymphoma (reticulum cell sarcoma, histiocytic lymphoma, immunoblastic sarcoma) in these patients is well known, this appears to be the first report of a granulocytic sarcoma. Granulocytic sarcoma, a rare tumor composed of immature granulocytic elements, almost never involves the parenchyma of the brain. Histochemical examination may be necessary to distinguish this lesion from other poorly-differentiated neoplasms.