Efficacy and Safety of Trastuzumab as a Single Agent in First-Line Treatment of HER2 -Overexpressing Metastatic Breast Cancer.
Charles L VogelMelody A CobleighDebu TripathyJohn C GutheilLyndsay N HarrisLouis FehrenbacherDennis J SlamonMaureen MurphyWilliam F NovotnyMichael BurchmoreSteven ShakStanford J StewartMichael PressPublished in: Journal of clinical oncology : official journal of the American Society of Clinical Oncology (2023)
3+ overexpression by IHC or gene amplification by FISH.