Cyclosporin A has been associated with an apparent increased incidence of non Hodgkins lymphoma, most often in conjunction with multiple immunosuppressive agents. We report a patient who developed a non Hodgkins lymphoma arising in the right tonsillar fossa six months following renal transplantation. The development of the lymphoma was associated with seroconversion for the Epstein Barr capsid antigen and nuclear antigen. The patient was receiving cyclosporin A alone as immunosuppression.