ERBB2 and colorectal carcinoma: The determining criteria for HER2 overexpression in CRC mainly refer to the HERACLES study (Sartore-Bianchi et al., 2016), which requires tumors with a 3+ HER2 score in over 50% of cells by immunohistochemistry or with a 2+ HER2 score and 50% of tumor cells to be FISH positive.