Genomic sequencing Examination of 733 HER2-amplified primary and metastatic breast tumours discovered important enrichment of mutations that activate RAS–MAPK signalling in advanced tumours addressed with prior anti-HER2 therapies121. These mutations, such as NF1 and HER2 activating mutations, contribute to resistance to tucatinib and neratinib. Long term clinical investigations will ... https://www.directivepublications.org/journal-of-clinical-breast-cancer/