Pathological Response and Survival after Neoadjuvant Therapy for Her-2 Positive Breast Cancer

Background: Pathological complete response (pCR) after neoadjuvant systemic treatment represents a good surrogate marker for the prognosis of Her-2 positive Breast Cancer (BCs). The results improved after adding anti-Her-2 therapy to chemotherapy in neoadjuvant setting. Methods: Our retrospective study enrolled a cohort of 56 invasive Her-2 positive non-metastatic BCs treated with neoadjuvant systemic therapy between 2001 and 2018. The patients received neoadjuvant chemotherapy with or without anti-Her-2 therapies before surgery and adjuvant endocrine and anti-Her-2 treatment together with adjuvant radiotherapy, based on clinical, pathological and hormonal receptor expression characteristics. The primary end point was pCR rate and disease-free-survival (DFS), defined as the interval between surgery and documented disease recurrence, progression, or death from any cause. Results: The rate of pCR for our patients was 41% independent of type of chemotherapy regimen and the anti-Her-2 therapy used. The results were improved by adding Trastuzumab in the neoadjuvant setting with statistical significance (p = 0.038). Median DFS was 68 months for the entire cohort. The risk of recurrence was higher in the group without pCR after neoadjuvant treatment (52% vs 17%; p = 0.003). 10 patients died (18%), all of them from group without pCR. The prognosis at 36-months was good, with 84% survival chance at 3 years follow-up. Conclusion: Our retrospective study underlines the positive impact of neoadjuvant systemic treatment on pCR rate and on disease-free survival in real-life Her-2 positive breast cancer patients.