Collecting Duct Carcinoma and Renal Medullary Carcinoma

Collecting duct carcinoma (CDC) and renal medullary carcinoma (RMC) are both rare and distinct subtypes of renal cell carcinoma (RCC) arising from the distal segment of the collecting ducts. Patients generally present with high-stage disease and median survival is significantly shorter than patients with more conventional RCC subtypes. RMC commonly affects younger, African American patients and almost all patients have a sickle cell hemoglobinopathy, most commonly sickle cell trait. Differential diagnoses include urothelial carcinoma, papillary RCC, and metastatic carcinoma. Patients with CDC and RMC are generally treated with surgical excision, followed by systemic chemotherapy, even though these tumors generally respond poorly to chemotherapy. However, due to the rarity of these tumors, studies of treatment outcome are limited to small case series and case reports, and more studies are needed to improve the outcome for these patients.