CDX2 and neoplasm: Immunohistochemistry showed strong membrane positivity for cytochrome 7 (CK7) (>90% tumor cells), cytochrome 20 (CK20)- focal membrane positivity in >20% tumor cells, cytochrome 19 (CK19)-focal positivity in 50-60% cells, and caudal type homeobox 2 (CDX2) was negative (Figure 8).