Prevalence of cancer history prior to renal transplantation.

Recurrent and de novo cancers contribute to morbidity and mortality post-transplantation. However, data on cancer prevalence in waiting list patients are lacking. The purpose of this study was to determine the prevalence of malignancy in patients considered for renal transplantation. Records of 382 potential renal transplant recipients were reviewed for the presence of malignant tumours. In 38 patients 45 tumours were detected. Forty-two malignancies were histologically confirmed, in three patients the evaluation was ongoing. Fourteen tumours were diagnosed before and 31 after initiation of dialysis. Overall cancer prevalence was 9.9%. For patients in the waiting list, the mean time from diagnosis of the malignancy was 2.2 years. Twenty of 45 (44%) tumours were located in the urinary system. The majority of malignancies was treated with a curative intention. Thus, 68% of patients with malignancies were listed as 'transplantable' or 'temporarily not transplantable'. From the waiting list, 13% were removed , 8% died and 11% had their evaluation halted because of their malignancy. Four patients received a transplant while eight patients died or were removed permanently from the list prior to transplantation. Death or removal from the list was as frequently related to tumour progression as to other causes (four patients each). A substantial number of waiting list patients had a history of malignancy. Future strategies have to identify patients at risk to assure intensive monitoring for recurrence, selection of patients who do not benefit from deferred transplantation and consideration of specific immunosuppressive protocols.