Cyclin依赖性激酶4/6抑制剂（CDK4/6i）与内分泌治疗（ET）的联合应用是激素受体阳性（HR + ）和人类表皮生长因子受体2阴性（HER2-）转移性乳腺癌（MBC）的标准治疗。目前尚无可靠的生物标志物可预测CDK4/6i的治疗反应，并且尚不清楚哪些患者从该治疗中受益。由于肝脏转移乳腺癌患者的预后较差，开发能够确定可能对CDK4/6i有反应的患者的预测性生物标志物具有临床重要性。本研究展示了在两个研究点接受帕博西尼布加内分泌治疗的73例已知存在肝转移的乳腺癌患者，在CDK4/6i治疗前后的几个周期内，通过影像纹理生物标志物来预测早期治疗反应和总生存期（OS）。Δ放射组学模型与验证集的OS相关（HR：2.4；95% CI，1.06-5.6；P = 0.035；C指数=0.77）。与RECIST反应相比，Δ放射组学特征以曲线下面积（AUC）=0.72，95%置信区间（CI）0.67-0.88预测治疗反应。本研究揭示了放射组学特征可以比标准解剖/RECIST 1.1评估更早地预测缺乏反应，并有待进一步研究和临床验证。© 2023. Springer Nature Limited.

The combination of Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) and endocrine therapy (ET) is the standard of care for hormone receptor-positive (HR + ), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC). Currently, there are no robust biomarkers that can predict response to CDK4/6i, and it is not clear which patients benefit from this therapy. Since MBC patients with liver metastases have a poorer prognosis, developing predictive biomarkers that could identify patients likely to respond to CDK4/6i is clinically important. Here we show the ability of imaging texture biomarkers before and a few cycles after CDK4/6i therapy, to predict early response and overall survival (OS) on 73 MBC patients with known liver metastases who received palbociclib plus ET from two sites. The delta radiomic model was associated with OS in validation set (HR: 2.4; 95% CI, 1.06-5.6; P = 0.035; C-index = 0.77). Compared to RECIST response, delta radiomic features predicted response with area under the curve (AUC) = 0.72, 95% confidence interval (CI) 0.67-0.88. Our study revealed that radiomics features can predict a lack of response earlier than standard anatomic/RECIST 1.1 assessment and warrants further study and clinical validation.© 2023. Springer Nature Limited.