ERBB2 and colorectal carcinoma: After demonstrating the accuracy of IHC/FISH scoring systems and cross-validation of NGS panels, the authors proposed new harmonized HER2 diagnostic criteria in CRC as follows: IHC 3+ score or IHC2+ score associated with HER2: CEP17 ratio > or =2 by FISH in more than 10% of tumor cells for surgically resected samples.