超声造影对小鼠乳腺癌淋巴结转移模型的诊断价值

Diagnostic Value of Contrast-enhanced Ultrasonography in Mouse Breast Cancer Lymph Node Metastasis Model

目的探讨经静脉超声造影(contrast-enhanced ultrasound,CEUS)对诊断小鼠乳腺癌淋巴结转移模型的应用价值。方法采用小鼠4T1乳腺癌细胞足垫种植成瘤的方法构建50只Balb/c小鼠腘窝淋巴结肿瘤转移模型,接种肿瘤细胞悬液后2~6周,每周随机抽取10只小鼠进行常规超声及CEUS检查,然后立即处死小鼠并解剖肿大腘窝淋巴结进行病理诊断,分析不同时间点淋巴结声像图表现及转移发生率。结果超声共检出50枚小鼠肿大腘窝淋巴结,其中经病理诊断为转移性淋巴结共32枚(32/50),反应性增生淋巴结18枚(18/50)。在CEUS上转移性淋巴结多表现为向心性的整体不均匀增强,反应性增生淋巴结多表现为离心性的整体均匀增强。常规超声在淋巴结良恶性鉴别中准确度为56.0%,灵敏度为56.3%,特异度为55.6%,联合经静脉CEUS在淋巴结良恶性鉴别中准确度为76.0%,灵敏度为75.0%,特异度为77.8%,联合CEUS的诊断准确度要高于单独常规超声(P<0.05),而灵敏度与特异度差异无统计学意义(P均>0.05)。结论经静脉CEUS对小鼠乳腺癌淋巴结转移模型的诊断有一定的应用价值。

Objective To explore the application value of intravenous contrast-enhanced ultrasound(CEUS)in the diagnosis of lymph node metastasis of breast cancer in mice.Methods The popliteal lymph node tumor metastasis model of 50 Balb/c mice was established by implanting 4T1 breast cancer cells in foot pad.Within 2-6 weeks after inoculation of tumor cell suspension,10 mice were randomly selected every week for routine ultrasound and CEUS examination.The mice were killed immediately and the enlarged popliteal lymph nodes were dissected for pathological diagnosis.The sonographic manifestations and metastasis rate of lymph nodes at different time points were analyzed.Results A total of 50 enlarged popliteal lymph nodes were detected by ultrasound,including 32 metastatic lymph nodes(32/50)and 18 reactive hyperplastic lymph nodes(18/50).On CEUS,most metastatic lymph nodes showed concentric enhancement and overall inhomogeneous enhancement,while reactive hyperplastic lymph nodes showed eccentric enhancement and overall homogeneous enhancement.The accuracy,sensitivity and specificity of conventional ultrasound in the differential diagnosis of benign and malignant lymph nodes were 56.0%,56.3%and 55.6%,respectively.The accuracy,sensitivity and specificity of combined transvenous CEUS in the differential diagnosis of benign and malignant lymph nodes were 76.0%,75.0%and 77.8%,respectively.The diagnostic accuracy of combined CEUS was higher than that of routine ultrasound alone(P<0.05),but there was no significant difference between sensitivity and specificity(P all>0.05).Conclusion Intravenous CEUS has a certain application value in the diagnosis of lymph node metastasis of breast cancer in mice.