Accuracy Of Ultrasound In Predicting Pathological Response During Neoadjuvant Chemotherapy Among Breast Cancer Subtypes

PurposesNeoadjuvant chemotherapy(NAC)is given to patients with locally advanced disease to help control locoregional disease and to improve the rate of breast conservation.Due to the existence of drug resistance,not all patients are sensitive to neoadjuvant chemotherapy.Monitoring the response to NAC in vivo can help to differentiate the responders from non-responders,allowing for timely individualization of therapy regimens to prevent overtreatment for responders or to shift to alternative therapies for non-responders.Breast cancer is a heterogeneous disease.The chemosensitivity and the patterns of tumor shrinkage after NAC vary according to cancer subtypes.Thus,the cancer subtypes may also influence the accuracy of imaging modalities.Ultrasound is the most accessible,cost-effective,and convenient modality to use to screen the mammary gland.So,the aim of our study is to explore the accuracy of ultrasound in predicting pathological response during neoadjuvant chemotherapy among breast cancer subtypes.ContentsFirst,we evaluate the accuracy of ultrasound in predicting pathological response during NAC among breast cancer subtypes.Then,we try to determine whether measurement parameters,response criteria,and assessment timing affect the accuracy of ultrasound.MethodsFrom 2011 to 2016,206 patients(69 hormone receptor [HR]+/human epidermal growth factor receptor 2 [HER2]-,43 HR-/HER2+,52 HR+/HER2+,and 42 triple-negative breast cancers [TNBC])were included in the retrospective study.The ultrasound response was tested via pathological examination.Receiver operating characteristic curve(ROC)analysis was used to test the predictive power of ultrasound.The sensitivity,specificity,and diagnostic odds ratios of three ultrasound response criteria were calculated and compared.ResultsROC analysis indicated that ultrasound can accurately predict pathological response in the TNBC group(P<0.05),but not in the HR+/HER2+ group(P>0.05).For HR+/HER2-and HR-/HER2+ group,delaying the assessment timing can improve the predictive power(P<0.05).The World Health Organization criteria applied to one diameter(WHO-1D)had the lower sensitivities with higher specificities among the four groups.Sensitivities and specificities were comparable between the Response Evaluation Criteria in Solid Tumors,version 1.1 and WHO criteria applied to two diameters(WHO-2D).ConclusionsUltrasound has the potential to accurately predict pathological response during the early stage of NAC in TNBC.For HR+/HER2-and HR-/HER2+ patients,delaying the evaluation timing of ultrasound may improve the accuracy.Meanwhile,other methods may be needed for HR+/HER2+ patients.RECIST 1.1 criterion performed better in TNBC and HR+/HER2-groups.For HR-/HER2+ and HR+/HER2+ patients,WHO-1D criterion has better diagnostic ability.