The recipient of a cadaver renal transplant survived five months with satisfactory renal function. The donor of the graft died from a bronchogenic carcinoma. There was no gross evidence of metastasis in the kidney at the time of nephrectomy in the donor. Four months after transplantation, malignant cells were seen in a biopsy of the grafted organ. This tumor was histopathologically identical to that in the donor. The recipient died from widespread metastasis of transplanted cancer five months following renal grafting.