目的 检测乳腺癌患者外周血糖类抗原15-3（CA15-3）、糖类抗原125（CA125）、癌胚抗原（CEA）、细胞角蛋白-18（CK18）、中性粒细胞与淋巴细胞计数比值（NLR）水平，探讨此5项外周血指标与乳腺癌患者临床病理特征、新辅助化疗效果的关系。 方法 回顾性分析2020年1月至2023年12月新乡市中心医院接受新辅助化疗的187例乳腺癌患者的临床资料，根据化疗8个周期后实体肿瘤的反应评价标准分为有效组（n = 84）和无效组（n = 103）。检测乳腺癌患者新辅助化疗前外周血CA15-3、CA125、CEA、CK18、NLR水平，比较不同临床病理特征乳腺癌患者的外周血CA15-3、CA125、CEA、CK18、NLR水平，比较有效组与无效组外周血CA15-3、CA125、CEA、CK18、NLR水平和临床资料。采用单因素和多因素logistic回归分析影响乳腺癌患者新辅助化疗无效的因素。绘制受试者工作特征（ROC）曲线分析外周血CA15-3、CA125、CEA、CK18、NLR预测乳腺癌患者新辅助化疗效果的效能。 结果 T₃ ~ T₄期、N₁ ~ N₃期、人表皮生长因子受体-2（HER-2）阳性的乳腺癌患者外周血CA15-3、CA125、CEA、CK18、NLR水平高于T₂期、N₀期、HER-2阴性的乳腺癌患者（P < 0.05）；无效组外周血CA15-3、CA125、CEA、CK18、NLR水平均高于有效组（P < 0.05）；无效组T₃ ~ T₄期、N₁ ~ N₃期、组织学分级为低分化、孕激素受体阳性、雌激素受体（ER）阳性、肿瘤增殖抗原高表达占比均高于有效组（P < 0.05）；外周血CA15-3、CA125、CEA、CK18、NLR水平升高、T₃ ~ T₄期、N₁ ~ N₃期、低分化、ER阳性均为影响乳腺癌患者新辅助化疗无效的危险因素（P < 0.05）；外周血CA15-3、CA125、CEA、CK18、NLR联合预测乳腺癌患者新辅助化疗效果的灵敏度、特异度、曲线下面积（AUC）分别为96.43%、82.52%、0.956，其中联合预测灵敏度、AUC均高于单独预测（P < 0.05）。 结论 外周血CA15-3、CA125、CEA、CK18、NLR水平可能与乳腺癌患者临床病理特征密切相关，并可能影响乳腺癌患者新辅助化疗效果，均能帮助预测乳腺癌患者新辅助化疗效果，但联合预测效能更佳。

Objective To assess the levels of peripheral blood markers including carbohydrate antigen 15-3 （CA15-3）， carbohydrate antigen 125 （CA125）， carcinoembryonic antigen （CEA）， cytokeratin-18 （CK18）， and neutrophil-to-lymphocyte count ratio （NLR） in breast cancer patients， investigate their correlation with clinicopathological characteristics， and evaluate the impact of neoadjuvant chemotherapy. Methods The clinical data of 187 patients with breast cancer who underwent neoadjuvant chemotherapy at our hospital between January 2020 and December 2023 were retrospectively analyzed. Based on the evaluation criteria for solid tumor response after 8 cycles of chemotherapy， the patients were divided into two groups： an effective group （n = 84） and an ineffective group （n = 103）. The levels of CA15-3， CA125， CEA， CK18， and NLR in the peripheral blood of breast cancer patients before neoadjuvant chemotherapy were measured. Furthermore， a comparison was made between the levels of CA15-3， CA125， CEA， CK18， and NLR in the peripheral blood among breast cancer patients with different clinicopathological characteristics. Additionally， a comparison was conducted between the levels of CA15-3， CA125， CEA， CK18，and NLR in the peripheral blood as well as clinical data between the effective group and ineffective group. Univariate and multivariate logistic regression analyses were employed to examine the factors influencing the ineffectiveness of neoadjuvant chemotherapy in breast cancer patients. Additionally， a receiver operating characteristic （ROC） curve was constructed to assess the predictive efficacy of peripheral blood markers including CA15-3， CA125， CEA， CK18， and NLR on the response to neoadjuvant chemotherapy in breast cancer patients. Results The levels of CA15-3， CA125， CEA， CK18， and NLR in the peripheral blood of breast cancer patients with T₃~T₄ stage， N₁~N₃ stage， and human epidermal growth factor receptor-2 （HER-2） positivity were significantly elevated compared to those in breast cancer patients with T₂ stage， N₀ stage， and HER-2 negativity （P < 0.05）. The levels of CA15-3， CA125， CEA， CK18， and NLR in the peripheral blood were found to be higher in the ineffective group than in the effective group （P < 0.05）. Moreover， a higher proportion of patients in the ineffective group exhibited T₃~T₄ stage tumors along with N₁~N₃ lymph node involvement. Additionally observed were histological grade of low differentiation as well as positive progesterone receptor and estrogen receptor expression. Furthermore high expression of tumor proliferation antigen was more prevalent among patients classified under the ineffective group. （P < 0.05）. Elevated peripheral blood CA15-3， CA125， CEA， CK18 and NLR levels， T₃~T₄ stage， N₁~N₃ stage， low differentiation， and ER positive were identified as significant risk factors for neoadjuvant chemotherapy in breast cancer patients （P < 0.05）. The predictive performance of peripheral blood CA15-3， CA125， CEA， CK18 and NLR in assessing the efficacy of neoadjuvant chemotherapy yielded a sensitivity of 96.43%， specificity of 82.52%， and an area under the curve （AUC） value of 0.956. Furthermore， combined prediction demonstrated higher sensitivity and AUC compared to individual predictors （P < 0.05）， while maintaining similar specificity levels. Conclusions The levels of CA15-3， CA125， CEA， CK18 and NLR in peripheral blood are closely associated with the clinicopathological characteristics of breast cancer patients and can impact the efficacy of neoadjuvant chemotherapy. These biomarkers have potential for predicting response to neoadjuvant chemotherapy in breast cancer patients， with improved accuracy when used in combination.