Abstract. We describe the development of a lymphoma in a liver allograft shortly after orthotopic liver transplantation. Aspiration and core biopsies of the nodule were persistently negative so that a diagnosis could not be made until the patient underwent retransplantation, when examination of the liver resection specimen revealed a B-cell lymphoma. Using a rapid technique based on the polymerase chain reaction, we were able to demonstrate that the tumor was of donor origin.
