Renal cell carcinoma most commonly originates from which part of the nephron?

Renal cell carcinoma most commonly originates from which part of the nephron?

• A. Glomerulus
• B. Proximal Convoluted Tubule
• C. Distal Convoluted Tubule
• D. Collecting Duct

Answer: (B)

Renal cell carcinoma most often starts in the proximal tubule epithelium of the nephron. The cells of the proximal convoluted tubule are highly metabolically active, with a prominent brush border and abundant cytoplasm rich in mitochondria. This makes them especially susceptible to malignant transformation, and their characteristic clear cytoplasm (from lipid and glycogen) is typical of the most common RCC type. The glomerulus is a filtration unit and is not a typical origin for RCC. Cancers arising from collecting ducts are rare and tend to have distinct features, while distal tubule–derived tumors are much less common than those from the proximal tubule.

Renal cell carcinoma most often starts in the proximal tubule epithelium of the nephron. The cells of the proximal convoluted tubule are highly metabolically active, with a prominent brush border and abundant cytoplasm rich in mitochondria. This makes them especially susceptible to malignant transformation, and their characteristic clear cytoplasm (from lipid and glycogen) is typical of the most common RCC type. The glomerulus is a filtration unit and is not a typical origin for RCC. Cancers arising from collecting ducts are rare and tend to have distinct features, while distal tubule–derived tumors are much less common than those from the proximal tubule.