Acquired Cystic Disease Associated Renal Cell Carcinoma Clinically Manifested as a Retroperitoneal Hematoma – Brief Presentation and Review of the Literature

Abstract Acquired cystic disease associated renal cell carcinoma is an entity first described in 2006 and recognized in the WHO (World Health Organization) guidelines of 2016, also present in the current edition, which develops in the context of chronic kidney disease. We present the case of a 61 years old patient with significant comorbidities, on hemodialysis for 15 years, who was admitted to the hospital’s Emergency Department for a retroperitoneal hematoma. The histopathological examination of the left nephrectomy specimen revealed polycystic kidney disease, chronic pyelonephritis, and a malignant neoplastic proliferation. Immunohistochemical tests established the diagnosis of acquired cystic disease associated renal cell carcinoma. The particularity of this case consisted in its clinical presentation, the incidental finding of the malignant renal tumor in the context of polycystic kidney disease, and the variable immunoexpression of the CK7 marker within the tumor tissue.