Renal transplantation and cancer. The Scandia transplant material

Between 1965 and 1973, 30 malignant tumours were found in patients transplanted in Scandinavia. Of these tumours, 24 were found in the 1,254 patients transplanted in Scandinavia as part of the Scandia Tranplant Programme between 1969 and 1972. Using the information recorded in the programme, 418 Danish patients who received their first and only transplant between 1969 and 1972 were selected and followed until 31/12 1973. Twelve tumours occurred in these patients. A comparison with the expected age, sex and time-specific incidence rates from the Danish Cancer Register was made and the observed tumour incidence was found to be significantly (P less than 0.001) greater than expected. Tumour incidence was found to be associated with incompatibility in the FOUR series, but was unrelated to number of rejections, the presence of HL-A antibodies and sex difference between donor and recipient. Apart from certain special forms of immunosuppression which could be oncogenic, the cause of tumour development appears to be multifactorial, both the allograft itself and immunosuppressive treatment playing a role.