Latent adenocarcinoma in renal cysts

A case is presented in which repeat examination of a benign cyst disclosed a latent adenocarcinoma near the cyst wall. Since statistically there is a greater incidence of tumor associated with cyst and since there is a 90% accuracy rate in the diagnosis of cystic lesions it appears that reinvestigation seems justified in some cases, especially if there is a change in or new development of symptoms.