Clinical application of HER-2 targeted therapy in patients with breast cancer

Molecular targeted therapy of breast cancer greatly improved the therapeutic effect of HER-2(human epidermal growth factor receptor-2) positive breast cancer.This study described several clinical applications in HER-2 targeted therapy,including recurrent or metastatic breast cancer needing re-biopsy for HER-2 detection.Patients could benefit from keeping using trastuzumab or changing to lapatinib even cancer progressed during trastuzumab treatment.As the NCCN guidelines recommend,patients with HER-2 positive and tumors 1 cm should receive chemotherapy combined with trastuzumab treatment.Currently the duration of standard treatment with trastuzumab is 1 year,however double targeted therapy has not been recommended as neoadjuvant therapeutic strategy described in the NCCN guidelines.Trastuzumab resistance might occur in the neoadjuvant,adjuvant,and metastatic therapy stages for HER-2 positive breast cancer and could be divided into primary resistance and acquired resistance.It is suggested to choose subsequent targeted therapy for patients according to resistance type in clinical practice.At the same time,we will continue to search the biomarkers associated with resistance.If so,patients could get maximum benefit from molecular targeted therapy.