Acquired multicystic transformation of kidneys.

Acquired multicystic renal transformation of diseased kidneys is a problem known since the early 19th century which has recently regained interest. Such cysts were known before dialysis was established, are seen prior to hemodialysis and in patients on peritoneal dialysis, and can therefore not be a consequence of hemodialysis. It is concluded that an increased incidence of renal cell carcinoma in such kidneys is not established, although, theoretically, several mechanisms might promote carcinogenesis in end-stage kidneys.