Abstract:

Objective

ToanalyzetheimpactofAR/p53/Ki-67expressionbeforeneoadjuvant chemotherapy on the efficacy and prognosis of triple negative breast cancer （TNBC） patients with HER-2 zero or low expression.

Methods

Clinical data of 122 patients with primary TNBC treated in the Department of Breast Surgery， Gansu Maternal and Child Health Hospital from January 2015 to December 2023 were retrospectively analyzed. Patients were divided into two groups based on HER-2 expression status： zero expression and low expression. Differences in AR/p53/Ki-67 expression and pCR rate after neoadjuvant chemotherapy between the two groups were compared using χ²test. Factors with statistically significant differences in univariate analysis are included in binary logistic regression analysis. Kaplan-Meier survival curves were plotted and compared using the log-rank test. Univariate and multivariate Cox proportional hazards models were used to analyze factors affecting disease-free survival （DFS）.

Results

Ki-67， HER-2， AR， and p53 expression were correlated with pCR rate in TNBC patients （χ²=6.829， 3.909， 4.483， 4.031， P=0.009， 0.048， 0.034， 0.045）. Multivariate logistic regression showed Ki-67 （OR=6.690， 95%CI：2.157-20.749， P＜0.001）， HER-2 （OR=0.404， 95%CI：0.172-0.950， P=0.038）， AR （OR=4.974， 95%CI：1.653-14.963， P=0.004）， and p53 （OR=2.450， 95%CI：1.027-5.844， P=0.043） were associated with pCR rate in TNBC patients. In HER-2-zero expression group， the pCR rate showed a significant difference between AR and Ki-67 negative or positive patients （40.4% vs 72.2%， χ²=5.426， P=0.020；22.2% vs 57.7%，χ²=6.735，P=0.009）. In HER-2-low expression group， AR/p53/Ki-67 expression was not correlated with pCR rates. The Cox regression showed clinical T stage was an independent factor for DFS（HR=0.203， 95%CI：0.084-0.493， P＜0.001）. In HER-2-zero expression group， DFS showed a significant difference between p53-positive and p53-negative patients （χ²=5.351， P=0.021）. AR/p53/Ki-67 expression was not correlated with DFS regardless of HER-2 status.

Conclusion

HER-2-low and HER-2-zero TNBC patients show a significant difference in pCR rates and prognosis， suggesting distinct underlying pathological and biological features that warrant further investigation.

Key words: Breast neoplasms, Receptor， erbB-2, Receptors， androgen, Neoadjuvant chemotherapy, Pathological complete response