Application Of Multimodality Ultrasound In The Diagnosis Of Benign And Malignant BI-RADS 4 Lesions

ObjectiveBreast cancer is currently the most common malignant tumor in the world of women,and the incidence is increasing.Many patients are often diagnosed with advanced breast cancer,so early diagnosis is the key to determine the prognosis of breast cancer patients.The fifth edition of the Breast Imaging Reporting and Data System(BI-RADS)quantifies the risk of malignancy in BI-RADS 4 lesions.The likelihood of malignancy is 2%-95%,and the risk span is large.It is recommended that a cytological diagnosis be performed to detect breast cancer as early as possible.Confirmed after pathology.The needle biopsy is an invasive examination,and the biopsy has certain limitations.BI-RADS 4 lesions overlap and cross on conventional ultrasound images.Some malignant nodules are easily misdiagnosed or missed due to atypical sonograms,and benign nodules may also undergo needle biopsy.To explore the application of multimodality ultrasound in the diagnosis of benign and malignant BI-RADS 4 lesions to improve the diagnostic sensitivity and accuracy and reduce unnecessary biopsy.Methods118 patients with BI-RADS 4 breast lesions were recruited from March 2016 to May 2017,aged 18-70 years.All the lesions were confirmed by core needle biopsy(CNB),vacuum-assisted biopsy(VAB)or pathology via surgery.The patients signed an informed consent form.Enhanced contrast-enhanced ultrasound imaging of the lesion,analysis enhancement mode,enhancement time,enhanced nodular morphology,area enlargement,presence of nourishing blood vessels around;Shear wave elastography(SWE)examination,the maximum elastic modulus of the nodule(Emax),the minimum value(Emin),the average elastic modulus value(Emean),and the ratio of the nodule to the surrounding tissue elasticity(Eratio)were obtained.Using the pathological results as the gold standard,ROC curve was used to analyze the value of conventional of US,CEUS,SWE and multimodal ultrasound diagnosis.Results1.Among the 118 cases of breast BI-RADS 4 lesions,74 were benign,including 45 cases of fibroadenomas,11 cases of intraductal papilloma,7 cases of adenosis,5 cases of dysplasia,2 cases of hamartoma,apocrine glands.2 cases of metaplasia,1 case of phyllodes tumor,1 case of inflammatory disease;44 cases of malignant group,including 36 cases of invasive carcinoma,7 cases of intraductal carcinoma,and 1 case of medullary carcinoma.2.Contrast-enhanced ultrasonography:between the benign and malignant lesions of the breast,the enhancement pattern,intensity and time,boundary morphology,area enlargement and radial nourishment were statistically significant(P<0.05)Benign nodules are characterized by fast-forward high-enhancement,slow-forward-low-enhancement,ascending-intensity enhancement or low-enhancement,internal enhancement is more uniform,post-enhancement boundary is clear,shape is regular,no expansion is manifested;malignant nodule angiography is more fast-forward and retreat or fast-forward and slow-return,the peak time is short,the peak intensity is high,the internal reinforcement is uneven,the area is obviously enlarged,and the surrounding area is radially enhanced.3.Shear wave elastography:the mean values of Emax,Emean,and Eratio in the malignant group(73.98±52.34 kPa,43.64±29.21 kPa,and 3.56±0.54)were higher than those in the benign group(34.23±13.66 kPa,23.14±8.80 kPa and 2.19±0.86).There were significant differences in the Maximum,Mean and Eratio values between the benign and malignant lesions(P<0.05).Emin was not statistically different between the two groups(P>0.05).When Emax was 54.9 kPa as the truncation,the diagnostic efficiency was the highest;the " Stiff rim sign" in the malignant lesions accounted for about 79.5%,which was significantly higher than the benign group(6.8%).4.Combined with conventional US,CEUS and SWE,the multimodal diagnostics are the most effective.The AUC of US+SWE+CEUS(0.973)was significantly higher than US(0.822),US+CEUS(0.918),US+SWE(0.965),but the difference was not statistically significant(P>0.05).Therefore,US+CEUS+SWE,US+SWE have better diagnostic performance.5.After re-classification by multi-mode ultrasound,the number of BI-RADS 3 and 4a lesions increased from 48 cases to 70 cases,and about 59.3%of lesions could avoid unnecessary biopsy.Conclusion1.US,CEUS and SWE have advantages in the diagnosis of BI-RADS 4 lesions,and all have important diagnostic value.The biological characteristics reflected by the three are different and cannot be replaced.2.The combined application of US,CEUS and SWE examination can improve the sensitivity and accuracy of ultrasound diagnosis of BI-RADS 4 lesions and it could reduce the biopsy rate,which has important clinical significance.