Assessing Curative Effect Of Neoadjuvant Chemotherapy In Breast Cancer By Magnetic Resonance Imaging Combined With Ultrasound

Objective:To investigate the clinical value of magnetic resonance imaging(MRI)combined with ultrasound(US)contrasting with MRI alone in evaluating the pathological complete response(pCR)of breast cancer after neoadjuvant chemotherapy(NAC).Methods:The clinical patients with breast cancer who received a complete cycle of neoadjuvant chemotherapy from December 2016 to December 2019 in the Breast Disease Diagnosis and Treatment Center of Affiliated Hospital of Qingdao University were collected and analyzed retrospectively.It includes the basic informations of these patients,such as age,and the pathological informations,including the size of tumor,lymph node status,pathological grading and molecular typing,chemotherapy,complete cycle of imaging examinations(MRI and US).According to the inclusion and exclusion criteria,a total of 146 patients were included.The results of MRI alone and MRI combined with ultrasound were designed into imaging of complete remission(r CR)and imaging of non-complete remission(non-r CR).1.With results of postoperative pathology as the gold standard,diagnostic checking was used to test the consistency between MRI alone and MRI combined with US in evaluating the curative effect of NAC,and kappa value was calculated.2.The sensitivity,specificity,and positive predictive value(PPV)of MRI alone and MRI combined with US in predicting pCR of patients were calculated.3.Consistency analysis and the related statistical indicators were further analyzed in the 4subtypes of breast cancer(HR~+/HER-2~+,HR~+/HER-2~-,HR~-/HER-2~+,and HR~-/HER-2~-subtype).Results:1.According to the inclusion and exclusion criteria,a total of 146 patients with primary invasive breast cancer were included,36 cases(24.7%)had a pCR after NAC.After NAC,22(78.6%)of the 28 patients evaluated by MRI alone achieved pCR,17(81.0%)of the 21 patients evaluated by MRI combined with US achieved pCR.The accuracy of assessing the curative effect of NAC by MRI alone was 86.3%(126/146),and the consistency(kappa)was 0.602 contrasting with pathological evaluation(P<0.001).The accuracy of assessing the curative effect of NAC by MRI combined with US was 84.2%(123/146),and the consistency(kappa)was 0.507 contrasting with pathological evaluation(P<0.00).The PPV value of pCR evaluated by MRI alone and MRI combined with US was 78.6%and 81.0%,respectively.2.Among the 146 patients,there were 34 cases of HR~+/HER-2~+subtype,63 cases of HR~+/HER-2~-subtype,23 cases of HR~–/HER-2~+subtype,and 26 cases of HR~–/HER-2~-subtype.36 cases had a pCR,among which 9 cases(26.5%)were in HR~+/HER-2~+subtype,10 cases(15.9%)were in HR~+/HER-2~-subtype,8 cases(34.8%)were in HR~-/HER-2~+subtype,and 9 cases(34.6%)were in HR~-/HER-2~-subtype.3.For the four subtypes,the accuracy of assessing the curative effect of NAC by MRI alone and MRI combined with US and the consistency(kappa)contrasting with pathological evaluation were analysed.Among the four subtypes,the accuracy of assessing the curative effect of NAC by MRI alone and the consistency were higher in patients with HR~+/HER-2~-subtype,HR~–/HER-2~+subtype,and HR~–/HER-2~-subtype,which were same in HR~+/HER-2~+.Both MRI alone and MRI combined with US showed the highest accuracy in patients with HR~+/HER-2-subtype breast cancer(92.1%and 85.7%,respectively);and the lowest accuracy in HR~+/HER-2~+subtype breast cancer(82.4%).MRI alone showed the highest consistency in patients with HR~-/HER-2~+subtype breast cancer(0.721),as MRI combined US showed the highest consistency in patients with HR~-/HER-2~-subtype breast cancer(0.620).4.Both MRI alone and MRI combined with US predicted NAC showed the highest PPV values in patients with HR~-/HER-2~-subtype breast cancer(85.7%and 100%,respectively),and the lowest values in HR~+/HER-2~-subtype breast cancer(71.4%and60.0%,respectively).Conclusion:1.For the overall patients with primary invasive breast cancer,Both MRI alone and MRI combined with US were all effective methods to assess the curative effect of neoadjuvant chemotherapy in breast cancer after NAC.MRI alone is superior to MRI combined with US in the test of accuracy and consistency.2.In the test of statistical related parameters,MRI combined with US is superior to MRI alone in evaluating the pathological complete response(pCR)of breast cancer after NAC,and among the patients with different subtypes of breast cancer,except HR~+/HER-2-subtype,MRI combined with US is still more effective in predicting efficacy after NAC than MRI alone.