[De novo malignant tumors during drug immunosuppression. The findings following 1245 cadaveric kidney transplants in 1080 patients].

Thirty new malignant tumours were found in 1080 patients (634 men, 446 women; mean age 37.6 +/- 13.6 years) after a median follow-up period of 5 years following 1245 cadaveric kidney transplantations performed between 1972 and 1990. The mean dialysis period before transplantation had been 4.0 +/- 3.1 years. Regarding the type of tumour, carcinomas were by far the most frequent, while there was only one lymphoma. The annual malignancy incidence for renal transplant patients was 0.5%. This is 3.5 times higher for men and 4.2 times for women than in the normal population. Immunosuppression with azathioprine and/or antithymocytic globulin (n = 395) produced the same malignancy incidence (0.54%) as with cyclosporin (n = 685; 0.60%). On the other hand, malignant tumours occurred much earlier under cyclosporin than under azathioprine/antithymocytic globulin (27 and 68 months, respectively).