Renal collecting (Bellini) duct carcinoma displays similar characteristics to upper tract urothelial cell carcinoma.

OBJECTIVES

To describe 3 cases of tumors located in the kidney that may relate collecting (Bellini) duct carcinoma (CDC) to urothelial cell carcinoma (UC). We hypothesized that these distinct tumor types may share a common origin. CDC is a subtype of renal cell carcinoma associated with a highly aggressive course, poor prognosis, and limited response to immunotherapy, behaving similarly to UC.

METHODS

We present 2 cases of CDC and 1 case of UC of the renal papilla. We compared the clinical presentation and survival rate, together with the radiologic, histologic, and immunostaining (including p53) findings, with strong emphasis on the similarities.

RESULTS

One patient with CDC had a previous history of grade 3, Stage Ta bladder UC. The urothelial carcinoma from the kidney papilla (case 3) presented carcinoma in situ of the adjacent urothelium and displayed mixed characteristics with CDC, namely location, positive staining for Ulex europaeus and pyelonephritic changes. p53 staining showed marked positivity in the tumor of patient 2. Disease progression was rapid, with a median survival of 5.6 months (range 5 to 7).

CONCLUSIONS

The results of this study suggest that the broad category of renal cell carcinoma includes a spectrum of lesions. In this range of diseases, CDC might be distinct from conventional renal cell carcinoma but share biologic features with UC, with the consequent implications for management. This association between CDC and UC may reflect the common embryologic origin of collecting duct and urothelial cells, since they derive from progressive branching of the mesonephric (wolffian) duct. Furthermore, the differential cytogenetic expression profiles suggest that the molecular events underlying the development of distal nephron and proximal tubule renal cancers are distinct.