Histology of renal carcinoma showing clear cells. Note the delicate vascular stroma. Histology of renal cell carcinoma showing granular cells. Spindle cell or sarcomatoid renal cell carcinoma. No epithelial-looking cells are present.
Venous invasion is often extensive in renal cell carcinoma.
Extension of the tumor into the renal vein is common and one of the common features of the disease is its tendency to metastasize hematogenously before giving rise to local symptoms and signs. Renal cell carcinoma with venous invasion. The tumor shows the typical yellowish color of renal cell carcinoma with foci of necrosis and cysts. Projecting from its cut surface is the cross-sectioned, thrombosed vein containing tumor. Renal cell carcinoma is one of the few carcinomas in which hematogenous metastases are more common than regional lymph node metastases.