HELENA: HER2-Low as a prEdictive factor of response to Neoadjuvant chemotherapy in eArly breast cancer

HER2 expression has a prognostic and predictive impact in early-stage breast cancer (BC). HER2 positive BC (immunohistochemistry (IHC) score 3+or 2+with in situ hybridization (ISH) amplifcation) are treated with HER2 targeted therapies.