Combined DCE-MRI And DWI For Predicting Breast Cancer Curative Effect After The Second Cycle Of Neoadjuvant Chemotherapy

Objective:To investigate the value of combining measurements from dynamic contrast enhanced magnetic resonance imaging（DCE-MRI）and diffusion weighted MRI（DWI）in the aspect of predicting breast cancer curative effect after the second cycle of neoadjuvant chemotherapy Methods:Forty eight cases who were treated by neoadjuvant chemotherapy in the Cancer Hospital of Shanxi Medical University were collected form 2014.1 to 2016.12.All patients were pathologically confirmed infiltrating ductal carcinoma and examined before NAC and after 2 cycles of treatment,then analyzed the quantitative parameters and ADC values.Histological response is categorized as major histological response（MHR）and non-major histological response（NMHR）.Pretreatment parameters were compared using independent samples t tests.Quantitative parameter and ADC values changes after 2 cycles of NAC were compared between MHR and NMHR using Mann-Whitney U test.The ADC changes and the better quantitative parameter were selected,then the step-wise logistic regression model was established and the new parameters were analyzed.Receiver operating characteristic curve（ROC）was used to evaluate the new parameter value in predicting breast cancer curative effect.Results:11 cases were concluded in the group of MHR and 37 cases in the NMHR.Pretreatment parameters(ADC,K^trans and K_ep)were 786±126 mm²/s,0.347±0.157min^-1 in the group of MHR and 0.936±0.349 min^-1 and 786±126 mm²/s,0.347±0.157 min^-1 and 0.936±0.349 min^-1 in NMHR.There was no significant difference between the two groups（t=-0.291,P=0.772;t=-0.055,P=0.956;t=-0.09,P=0.928）.The parameter changes after 2 cycles of NAC were 51.2%,-65.1%,-64.7% in the group of MHR and 31.2%、-11.8%、-24.9% in the group of NMHR.There was significant difference between the two groups（Z=-2.735,P=0.006;Z=-3.496,P=0.000;Z=-3.226,P=0.001）.The area under curve（AUC）were 0.774,0.850,0.823 and 0.894.The best AUC is new parameters.Conclusion:The parameter changes of ADC,K^trans and K_ep could predict final pathologic response in the breast cancers after 2 cycles of NAC.Combined ADC values and K^trans after 2 cycles of NAC was superior to single-parameter measurements for predicting final pathologic response.