Noninvasive axillary lymph node staging for early-stage breast cancer by ultrasound examination:a preliminary clinical study / 军事医学

ABSTRACT

Objective To investigate the clinical value of axillary ultrasound (AUS)in the identification of axillary nodal metastasis (ALNM).Methods Two hundred and eighty-two consecutive patients with stage Tis-T2 breast cancer were prospectively enrolled between December 2013 and September 2015.All the patients underwent AUS performed by two specified senior ultrasound doctors.Sonographic features of their axillary lymph nodes (longitudinal and transverse diameters,cortical and hilar thickness,blood flow form)were collected.These patients were divided into metastatic, suspicious and non-metastatic groups based on the ultrasound features by ultrasound doctors.The diagnostic accuracy of AUS was compared with results of pathology.Univariate and multivariate Logistic regression analyses were used to evaluate the relationship between sonographic features and ALNM.The area under the ROC curve was used to assess the accuracy of the multivariate Logistic regression model.Results The sensitivity,specificity,positive and negative predictive value and accuracy of AUS were respectively 85.6%,87.1%,86.4%,86.3%,and 86.3% in the metastatic and non-metastatic groups.The Kappa value was 0.727(P <0.001).The ALNM burden in the non-metastatic group was significantly lower than in the metastatic group (1.2 vs 6.9,P <0.001).The false-negative results were found only in 16 cases,fourteen of whom had only 1,and two had 2 and 3 ALNM,respectively.Univariate Logistic regression analysis showed that maximum cortical thickness was the most significant predictive factor of ALNM(the area under the ROC curve was 0.872).Multivariate Logistic regression analysis suggested that cortical thickness and the ratio of hilar thickness to cortical thickness were predictive factors of ALNM(P <0.05).The area under the ROC curve of the multivariate Logistic regression model was 0.879 and its sensitivity and specificity were 77.0% and 85.1%,respectively.Conclusion AUS is a valuable tool for detecting ALNM.Patients with false-negative results of AUS have a lower axillary metastatic burden.Maximum cortical thickness is the most significant predictive factor of ALNM.AUS may be a potential alternative method for sentinel lymph node biopsy as axillary lymph node staging in early-stage breast cancer patients.