In summary, the susceptibility of transplant recipients to the development of cancer is dramatically revealed by the oncogenic effects of sunlight. Skin and other forms of carcinoma are aggressive and develop particularly in patients doing well from the immunological point of view post transplantation. Patients with cancer are less susceptible to rejection than those without. Patients with malignancy survive significantly better in the early post transplant years than do those without cancer, but fare much worse later on because of deaths caused by cancer and because of the need to withdraw immune suppressive therapy in those patients with proliferating cancer. Almost 40% of long survivors have cancer, an incidence which continues to increase. Cancer has become a major cause of mortality in long survivors. It seems that, with time, most carcinomas which occur in the general population will occur with increased frequency in renal transplant recipients.