Neoadjuvant pertuzumab plus trastuzumab in combination with chemotherapy for human epidermal growth factor receptor 2 positive breast cancer: a real-world retrospective single-institutional study in China

Real-world studies on neoadjuvant dual anti-HER2 therapy combined with chemotherapy for breast cancer (BC) are scarce in China. This study aimed to evaluate the efficacy and safety of neoadjuvant dual anti-HER2 therapy combined with chemotherapy in a real-world setting. Moreover, differences in estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and proliferation cell nuclear antigen (Ki-67) expression pre- and post-neoadjuvant therapy were analyzed. Clinical and pathological data of patients with HER2-positive BC who received neoadjuvant dual anti-HER2 therapy combined with chemotherapy at Liaoning Cancer Hospital Institute, China, between September 2021 and September 2023, were retrospectively reviewed. Among 179 included patients, a pathologic complete response (pCR) was achieved in 109 patients (60.9