Patterns of Care and Clinical Outcomes of First-Line Trastuzumab-Based Therapy in HER2-Positive Metastatic Breast Cancer Patients Relapsing After (Neo)Adjuvant Trastuzumab: An Italian Multicenter Retrospective Cohort Study

Abstract

Despite the inferior median PFS, trastuzumab-based therapy was an effective first-line treatment for patients relapsing after (neo)adjuvant trastuzumab. Previous trastuzumab exposure and the respective TFI, type of first site of disease relapse, and hormone receptor status should be considered in the choice of the best first-line treatment option for HER2-positive metastatic breast cancer patients.