To explore the application of ultrasound-guided core-needle biopsy(CNB) and frozen section analysis (FSA) in the diagnosis of breast tumor.

A total of 51 patients with breast tumor who needed biopsy in the Department of General Surgery, Fuzhou General Hospital of PLA from September 2017 to February 2018 were included in this prospective study. The postoperative histopathologic diagnosis was used as the gold standard and Kappa consistency test was used to evaluate the accuracy of CNB plus FSA.

Thirty-five patients were diagnosed with breast cancer cells by CNB plus FSA, and all of them were confirmed malignant by postoperative pathology. Among 16 patients with no cancer cells in CNB plus FSA, 4 patients were malignant and 12 patients were benign in postoperative pathology. The false negative rate was 10.3%(4/39), accuracy 92.2%(47/51), sensitivity 89.7%(35/39), specificity 12/12, false positive rate 0 (0/12), positive predictive value 100%(35/35), negative predictive value 12/16, negative likelihood ratio 0.103 and Youden index 0.897. There was no significant difference between the result of CNB plus FSA and postoperative histopathologic result (χ²=2.250, P=0.125). The Kappa test showed a good consistency between CNB plus FSA and postoperative histopathology (Kappa=0.805, P<0.001). The factors including age, location of lesion, mammography and lesion size had no effect on the accuracy of CNB plus FSA (all P >0.050; χ²=3.074, P=0.266). The accuracy of CNB plus FSA in patients with elastography score ≥ 4 was significantly higher than that in patients with elastography score <4 [100%(37/37)vs 10/14, P=0.004]. BI-RADS grade of color ultrasound had effect on the accuracy of CNB plus FSA (χ²=15.432, P<0.001). The accuracy of CNB plus FSA in patients with BI-RADS ≥ 4 was significantly higher than that in patients with no BI-RADS grade [100% (36/36) vs 1/4, P<0.017]. The accuracy of CNB plus FSA in patients with elastography score ≥ 4 was 10.57-fold as high as that in patients with elastography score<4. The accuracy of CNB plus FSA in patients with definite BI-RADS grade was 35.25-fold as high as that in patients with no BI-RADS grade.

CNB plus FSA can be used in the diagnosis of breast tumor, with the advantages of minimal invasive operation and fast detection, however, there are some false negative cases and low negative predictive value. If the result is negative, the tumor should be confirmed by biopsy. The elastography score and BI-RADS grade of color ultrasound can influence the accuracy of CNB plus FSA.