Real-world data of subcutaneous trastuzumab and intravenous pertuzumab as neoadjuvant therapy for localized HER2+ breast cancer in Panama

Abstract

The aim of this study is to determine the effectiveness of subcutaneous trastuzumab in combination with intravenous pertuzumab and chemotherapy for patients with HER2-overexpressing localized breast cancer treated in our center. Methods: This was a descriptive, retrospective, real-world study. Results: Of 156 patients, pathological complete response (pCR) was achieved in 64.1%. A multivariate analysis showed a relationship with a negative hormone receptor (HR) expression and a HER2 score of 3+ by immunohistochemistry. Relapse-free survival (RFS) was higher in patients with pCR. Conclusion: Neoadjuvant therapy with dual blockade using intravenous pertuzumab and subcutaneous trastuzumab for HER2+ localized breast cancer in routine clinical practice resulted in a 64.1% pCR rate. Additionally, this outcome was related to a negative HR expression and HER2 overexpression, and correlated with higher relapse-free survival.