The ERBB2 gene (Fig1) which encodes for Her2 is a major proliferative driver for several cancer types. Gene amplification
and protein expression are associated with sensitivity to Her2-targeting drugs. In some cancer types ERBB2 mutations may be more relevant in carcinogenesis than gene amplification or protein expression. The mutation spectrum of ERBB2 in solid tumors is relatively unknown. The emergence of NGS methodology had enabled high throughput detection of both
known and novel oncogenic mutations in human genome including the presence of activating mutations of ERBB2.