Therefore, it should be remembered that CDX2 - CK20 - CRCs can metastasize to the liver.13 Notably, a significant proportion of breast carcinoma (35.7%) and gastric adenocarcinoma (33.3%) cases were CK7- CK20+, which suggests that this finding could be due to changes in the immunoprofile of metastatic tumors or expression loss related to treatment effects. This evidence concerns the gene CDX2 and breast carcinoma.