Renal neoplasias in patients receiving dialysis and renal transplantation:Clinico-pathological features and P53 gene mutations

Background. In Japan, the relative risk for renal cell carcinoma (RCC) in r enal transplants was about 80-fold higher than that in the general populati on, Depressed immune surveillance due to the use of immunosuppressive agent s was considered to cause cancer. Before renal transplantation, a vast majo rity of patients received hemodialysis, a known causative factor for acquir ed cystic disease of kidney (ACDK). Because ACDK is also considered to pred ispose to RCC, at least two risk factors for cancer accumulate in renal tra nsplants. Methods. In our study, clinicopathological features together with p53 gene mutations were analyzed in 218 patients with RCC: 22 received dialysis foll owed by renal transplantation, 39 received dialysis alone, and 157 sporadic RCC, P53 mutations were analyzed on DNA extracted from paraffin-embedded s pecimens with use of single strand conformation polymorphism, followed by d irect sequencing. Results. RCC in transplants shared several clinicopathological features wit h those in dialysis patients, which included small size and multiplicity of tumor, relatively high frequency of presence of ACDK, and papillary type o f RCC, p53 gene mutations were infrequent in RCC of any clinical setting. Conclusions. Atrophic kidney at the end-stage of renal failure and under di alysis have lesions of ACDK that might predispose to RCC in dialysis and tr ansplant patients.