Patients with renal failure who undergo dialysis for years may develop multiple cysts in their kidneys. This is probably the result of obstruction with progressive interstitial fibrosis in end-stage renal disease. There may be hemorrhage into the cysts. When such cysts develop, they are more numerous than the common simple renal cysts, but usually less numerous than the cysts with DPKD, and the size of the kidneys with dialysis-induced cystic disease is usually not markedly increased, as it is with DPKD. There is an increased risk for development of renal cell carcinoma.