Pathological Complete Response with Neoadjuvant Trastuzumab Combined with Chemotherapy in HER2 Positive Breast Cancer: A Single Institution Retrospective Analysis from Vietnam

Abstract

Purpose

Neoadjuvant regimens containing trastuzumab and chemotherapy were widely used in human epidermal growth factor 2 (HER2) positive breast cancer patients. In this article, we report complete pathological response (pCR) rates from a single institution in Vietnam.

Patients and Methods

Medical records of HER2 positive breast cancer patients who received neoadjuvant treatment with trastuzumab combined with chemotherapy were reviewed. Information on patient demographics, breast cancer stage, pathology reports, surgical data, and treatment regimens were collected. Pathological response was evaluated using Chevallier’s criteria, in which complete pathological response was defined as yT0yN0 or yTisN0.

Results

Thirty-nine eligible breast cancer patients treated with chemo-trastuzumab combined regimens in a neoadjuvant setting at Vietnam National Cancer Hospital were included in the analysis. Median age was 47 (range 32–72 years). Of these 39 patients, 5 (12.8%) were at stage II and 34 (87.2%) were at stage III. Median tumor size was 5.8 cm. There were 22 (56.4%) and 17 (43.6%) patients who had hormone receptor (HR) negative and positive diseases, respectively. Pathological complete response in the breast was demonstrated in 30 out of 39 (76.9%) patients. Of 35 patients with lymph nodal involvement, axillary pCR occurred in 25 (71.4%) patients. Total pathological complete response (tpCR) was achieved in 25 (64.1%) of the evaluated patients. There was no significant association between pathological response rates and age, tumor grade, hormone receptor status, and Ki-67 expression.

Conclusion

Neoadjuvant treatment with trastuzumab and chemotherapy combined in patients with HER2 positive breast cancer yielded a pathological complete response rate of 64.1%.

Keywords:

• pathological response
• neoadjuvant
• breast cancer
• trastuzumab
• chemotherapy

Ethical Consideration

This study complied with the 1964 Helsinki Declaration and its later amendments. All the data collected from patient file were treated confidentially and in compliance with relevant data privacy policies.

The protocol of this study was approved by the National Cancer Hospital of Vietnam, by the Decision numbered 797/QĐ – BVK in 2018.

Disclosure

The authors declared that they have no conflicts of interest related to this study.