The Ki67 index of preoperative breast cancer puncture is correlated with lymph node metastasis, ER, PR and AR expression: A retrospective study of real world data

Objective Breast cancer is a prevalent malignant disease among women. Currently, the primary clinical treatment strategies involve classifying breast cancer based on the expression of Ki67, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2), followed by endocrine or chemotherapy. Through the retrospective analysis of a real world data, this study explored the Ki67 index and clinicopathological features of breast cancer patients before operation and the clinical significance of neoadjuvant therapy. Methods Clinicopathological characteristics and preoperative immunohistochemistry (IHC) results for the Ki-67 index and ER, PR, Androgen receptor (AR), and HER-2, were collected from patients who underwent modified radical mastectomy at Baoji Central Hospital between June 2024 and June 2025. Using 30% as the cutoff value for the Ki-67 index, the chi-square test was used to compare differences in clinicopathological and immunohistochemical features between the low- and high-Ki-67 index expression groups. Results The results suggest that the preoperative puncture Ki67 index of breast cancer patients is significantly related to lymph node metastasis (LNM), ER, PR and AR expression. Univariate survival analysis showed that MKI67, ERS1, AR and ERBB2 had no significant effect on overall survival (OS) and progression-free survival‌ (PFS) ( P  > 0.05), while PGR had significant statistical significance on PFI ( P  < 0.05) and no significant effect on OS ( P  > 0.05). Multivariate survival analysis showed that the gene sets of MKI67, ESR1, PGR, AR and ERBB2 had no significant effects on OS and PFS, but PGR might have marginal effects on OS ( P  = 0.0523). C onclusion: Ki67 stratification based on early breast cancer patients can predict the expression of LNM, HR and AR, and provide scientific basis for individualized neoadjuvant therapy. However, Ki-67 index does not have the potential to judge the survival prognosis, and more potential IHC characteristics should be explored as new biomarkers to predict the prognosis and long-term survival of neoadjuvant therapy.