These metastases were positive for PAX8, that is a well-established marker for primary and metastatic RCC (Ozcan et al., 2012; Shen et al., 2012) and CDH16, which is a specific renal protein (Shen et al., 2012), while they were negative for the bile ducts and cholangiocarcinoma marker CK7 (Cytokeratin 7), consistent with their renal origin (Figure 2L). Here, CDH16 is linked to renal cell carcinoma.