KRT7 and neoplasm: Diagnosis of metastatic renal cell carcinoma (RCC) was confirmed by immunohistochemical stains, which showed the tumor cells to be positive for CD10 (Figure 5), vimentin (Figure 6) and pancytokeratin, but negative for CK7, carcinoembryonic antigen (CEA), chromogranin, synaptophysin and CD68.