Neoadjuvant Therapy and Axillary Lymph Node Status in HER2-Positive Breast Cancer

Abstract

Based on an estimating model, the aim of our study was to evaluate the axillary lymph node involvement of patients with primary invasive early human epidermal growth factor receptor 2 (HER2)-positive breast cancer before receiving neoadjuvant therapy (NAT). Patients with primary surgery (n = 63) were compared with patients who had received NAT (combined chemo/HER2-targeted antibody therapy) before surgery (n = 152). In patients receiving NAT, a positive N stage was estimated in 73.2 (49.8%) tumors resulting in a conversion (positive N stage-ypNpositive) of 35.5%. In 126 cases with ypN0 stage, a positive N stage was estimated in 41.4%.

Keywords:

• HER2-positive breast cancer
• neoadjuvant therapy
• pathological node stage
• axillary response
• estimating model

Authors’ Contributions

SD, CP, SW, and CFS contributed to study conception and design. SD, KTS, and CFS provided the findings and contributed to the literature search. SD, SW, and CFS contributed to collection and assembly of data. All authors contributed to data analysis and interpretation. SD, CP, SW, and CFS contributed to writing the manuscript. All authors contributed to the review and approval of the manuscript.

Ethical approval

The study has been approved by the ethics committee of the Medical University of Vienna.

All procedures performed in our study were in accordance with the ethical standards of the institutional committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. According to the ethics committee of the Medical University of Vienna, written informed consent was not required owing to the retrospective design of the study.

Disclosure statement

The other authors report no conflict of interest.

Data availability statement

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

There is no funding of the study.

Notes on contributors

Sabine Danzinger

Sabine Danzinger has received speaker honoraria from AstraZeneca, Eli Lilly, and Roche; has served as an advisor to Roche; and has received travel expenses from Amgen, Eli Lilly, Merck Sharp & Dohme (MSD), Novartis, Pfizer, Roche, and Sandoz.

Kristina Tendl-Schulz

Kristina Tendl-Schulz has received honoraria for lectures or advisory board participation from Roche as well as travel support from Roche, Novartis and Merck Sharp and Dohme GmbH (MSD).

Christian F. Singer

Christian F. Singer has received speaker honoraria as well as travel support and research funding from Novartis, AstraZeneca, Pfizer, Amgen, and Roche.