Comments: The yellow-white nodules had the typical morphology of conventional renal cell carcinoma, clear cell type. The solid, creamy-white, firm-appearing areas in between the nodules showed sarcomatoid change. (Photo courtesy of: Dr. Kyle Molberg, UT Southwestern Med. Ctr., Dallas)
Comments: Approximately 5% of renal cell carcinoma cases show sarcomatoid change. The sarcomatoid areas generally show features of MFH, fibrosarcoma, or undifferentiated spindle cell sarcoma (seen in this case).
