[Renal carcinoma in hemodialysis patients. Specially concerned with acquired cyst]

Acquired cystic disease of the kidney (ACDK) with carcinoma in the original kidney is one sensational complication of long-term hemodialysis patients. The rate of incidence is about forty times higher than that in the general population and especially high in the young male group. From Dec. 1978 to Nov. 1990, we identified 8 patients of ACDK by computerized tomography (CT) scan, sonographic examination and angiography. Most patients had no clinical symptoms. The mean term of hemodialysis of the patients was 8 yrs. And one patient was diagnosed as having ACDK and tumor 8 yrs after kidney transplantation and then the kidney was removed. Their mean age was about 32 y.o. and the tumor size 1-3 cm in diameter. All tumors were inside the renal capsule. (Robson-1) Pathohistologically, the tumor area consisted of mainly clear cell carcinoma and the epithelium of the cyst wall showed multi-layered or papillary hyperplasia. In the 1st and 7th cases, simple nephrectomy was performed by transperitoneal approach. In the other cases it was performed by flank incision. All cases have had no recurrence and no metastasis of renal carcinoma. The etiology of ACDK and carcinoma occurrence has not been clarified yet, but it is suggested that uremic metabolite and deficiency of immuno-surveillance may cause the pathological changes in kidney tissue.