Collecting Duct of Bellini Renal Carcinoma

Collecting duct carcinoma or Bellini duct carcinoma is a very rare variant of kidney carcinoma, characterized by an aggressive course and an extremely poor prognosis [1-4,5]. Unlike the more common variants of renal cell carcinoma that arise from the convoluted tubules of the renal cortex, this aggressive malignancy is derived from the renal medulla, possibly from the distal collecting ducts of Bellini. Another distinctive feature of collecting duct carcinoma is its propensity for showing infiltrative growth, which differs from the typical expansile pattern of growth exhibited by most renal malignancies at pathologic examination [2]. Collecting duct carcinomas demonstrate an aggressive clinical course. Less than one-third of patients survive more than 2 years beyond diagnosis, and up to 40% have metastatic disease at presentation [3].