# Association between pathologic complete response and biochemical indicators after neoadjuvant therapy for HER2-positive breast cancer

## TL;DR

This study explores how changes in blood lipid levels during treatment for a specific type of breast cancer may predict treatment success.

## Contribution

The study identifies that fasting triglyceride levels during treatment may predict pathologic complete response in certain HER2-positive breast cancer subgroups.

## Key findings

- Lower fasting triglyceride levels during neoadjuvant therapy are associated with higher likelihood of pathologic complete response in ER-negative HER2-positive breast cancer.
- Fasting triglyceride levels may serve as a predictive biomarker for treatment response in PR-negative HER2-positive breast cancer.
- Lipid management during treatment could offer both short-term and long-term benefits for some patients.

## Abstract

This study investigated the changes in the fasting blood glucose (FBG), fasting triglyceride (FTG), and fasting total cholesterol (FTC) levels during neoadjuvant therapy (NAT) for human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC) and the association with pathologic complete response (pCR).

Relevant data from Sichuan Cancer Hospital from June 2019 to June 2022 were collected and analyzed, and FBG, FTG, and FTC were divided into baseline, change, and process groups, which were grouped to analyze the changes after receiving NAT and the association with pCR.

In the estrogen receptor (ER)-negative subgroup, patients with low levels of FTG in the process group were more likely to achieve pCR compared to high levels, and in the progesterone receptor (PR)-negative subgroup, patients with lower FTG compared to higher FTG after receiving NAT was more likely to achieve pCR.

Patients with HER2-positive BC undergoing NAT develop varying degrees of abnormalities (elevated or decreased) in FBG, FTG, and FTC; moreover, the status of FTG levels during NAT may predict pCR in ER-negative or PR-negative HER2-positive BC.Early monitoring and timely intervention for FTG abnormalities may enable this subset of patients to increase the likelihood of obtaining a pCR along with management of abnormal markers.

• Neoadjuvant therapy causes various fasting glucose, fasting triglyceride, and fasting cholesterol abnormalities.

• Fasting triglycerides may predict the pathologic complete response in some patients.

• Fasting blood glucose and fasting total cholesterol do not predict the pathologic complete response.

• Some patients may derive both short-term (achievement of pathologic complete response) and long-term (reduction of cardiovascular disease risk) benefits in conjunction with lipid management.