Renal collecting duct carcinoma: report of a case with unusual imaging findings regarding renal function.

Renal collecting duct carcinoma (CDC) is a rare and aggressive type of renal cell cancer (RCC), which is difficult to confirm before surgery. We present a case of CDC presenting a hypovascular mass on renal CTA and deteriorated renal function of the affected kidney on single photon emission computed tomography (SPECT), which are different from the most common RCC, clear cell RCC. Considering these findings, it would be worthwhile investigating the role of CTA and SPECT in CDC diagnosis.