Serum HER2 Level Predicts Therapeutic Efficacy and Prognosis in Advanced Breast Cancer Patients

Abstract

Background

The purpose of this study was to investigate the therapeutic efficacy and prognosis of serum HER2 (sHER2) in patients with advanced breast cancer.

Methods

We analyzed the sHER2 levels of 200 patients with advanced breast cancer receiving first or second line treatment, the tissue HER2 (tHER2) level was also analyzed. Indicators of therapeutic efficacy and prognosis were objective response rate (ORR), disease control rate (DCR), and time to progression (TTP).

Results

The baseline sHER2 level was high in 132 patients and low in 68 patients. The high level of sHER2 is correlated with molecular subtype (p=0.016), visceral metastasis (p<0.001), liver metastasis (p<0.001), tissue HER-2 (tHER2) (p=0.001), and, among tHER2-low tumors (59 patients), the baseline sHER2 high level was associated with a higher proportion of brain metastasis. The ORR of patients with baseline sHER2 high level is higher than those with baseline sHER2 low level (p=0.026). The TTP of patients with baseline sHER2 low level is longer than the patients with baseline sHER2 high level (p=0.024). For patients with baseline sHER2 high level, a significant decrease in sHER2 after two cycles of treatment indicates higher ORR, DCR, and an extension of TTP. After multiple cycles of treatment, for patients with tHER-2 positive and baseline sHER2 high level, the DCR in the sHER2 decrease in the negative group was higher than that in the continuous positive group (p=0.037). Patients with a rapid decline type of sHER2 dynamic change curve had higher ORR and prolonged TTP compared with patients with other types of sHER2 dynamic change curve. There is no correlation between OS and sHER2 levels.

Conclusion

Our study showed that patients with advanced breast cancer had a high level of sHER2 at recurrence, regardless of whether they are tHER2 positive or negative. Dynamic detection of sHER2 can help predict therapeutic efficacy and prognosis, regardless of whether tHER-2 is positive or negative.

Keywords:

• serum HER2
• advanced breast cancer
• clinicopathological characteristics
• therapeutic efficacy
• prognosis

Ethics Approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. This study was approved by The Ethics Committee of Tianjin Medical University Cancer Institute and Hospital (Ek2017067). Informed consent of study participants was obtained prior to study commencement. We declared that patient data was confidential.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising, or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

The authors declare that they have no conflicts of interest in this work.

Additional information

Funding

This study was funded by National Natural Science Foundation of China (81602340, 81472183); Tianjin Key Medical Discipline (Specialty) Construction Project (TJYXZDXK-009A, TJYXZDXK-012A); Tianjin Medical University Cancer Hospital “14th Five-Year” Peak Discipline Support Program Project; Shenzhen Chipscreen Biosciences project; Science and Technology Project of Tianjin Health Commission (Grant NO, TJWJ2021MS009).