Purpose To analyze the impact of clinicopatho-logical factors on residual tumor burden(RCB)grading system and Miller-Payne(MP)grading system in non-specific invasive breast cancer patients after neoadjuvant chemotherapy,and to explore the predictive value of the two grading systems for patient survival.Methods The clinical data of 177 patients with non-specific invasive breast cancer diagnosed by preoperative punc-ture and treated with neoadjuvant chemotherapy were retrospec-tively analyzed.The relationship of RCB grading system or MP grading system with disease free survival(DFS)and overall sur-vival(OS)was studied,and the value of the two systems in predicting prognosis was analyzed and compared.Results RCB grading was related to menstrual status,histological grading be-fore treatment,and lymph node metastasis after treatment;MP grading was related to pre-treatment histological grading,post-treatment lymph node metastasis,and pre-treatment molecular typing.By evaluating the ROC curve of recurrence and survival and comparing the area under curve(AUC),it was shown that RCB grading system was superior to MP grading system in pre-dicting recurrence and evaluating survival.Univariate and multi-variate survival analysis showed that pre-treatment clinical stag-ing,post-treatment lymph node metastasis,and RCB grading were independent factors for DFS.Pre-treatment clinical stag-ing,pre-treatment molecular typing,and RCB grading were in-dependent factors for OS,while MP grading was not an inde-pendent factor for DFS and OS.Conclusion RCB grading sys-tem has a higher predictive value for patient survival than MP grading system.RCB grading evaluation system is recommended as evaluation system for non-specific invasive breast cancer after neoadjuvant chemotherapy.

Objective To observe the value of apparent diffusion coefficient(ADC)for quantitatively evaluating progressive muscle injury of rabbit limbs in early stage of high-voltage electrical burn.Methods Twenty healthy adult rabbits were selected to establish limb high-voltage electrical burn models,which were randomly divided into 0.5,24,48 and 72 h groups(each n=5).MR diffusion weighted imaging(DWI)was collected for each group at 0.5,24,48 and 72 h after modeling,and the injured core muscles of the right hind limb and the normal muscles of the contralateral limb were taken for HE staining.The muscle's ADC,muscle fiber density(MFD)and muscle fiber diameter(D)values at the injured core of current entry and exit were compared,and those of normal muscle were also analyzed.The correlations of ADC values in injured core muscle and MFD or D values were investigated.Results There were significant differences of ADC values of injured core muscle at both the entry and exit and normal muscle,also of ADC values of injured core muscle at the entry and exit within each group(all P＜0.05).ADC values of injured core muscle at the entry and exit decreased with time going(all P＜0.05),but ADC values of normal muscle were not significantly different among different time points(P＞0.05).MFD values of injured core muscle at the entry and exit decreased with time going(all P＜0.05),while MFD values of the normal muscle,D values of the injured core muscle at the entry and exit and normal muscle were not significantly different among time points(all P＞0.05).ADC value of the injured core muscle was positively correlated with MFD value and negatively correlated with D value(rs=0.846,r=-0.507,both P＜0.05).Conclusion ADC could quantitatively evaluate the progressive muscle injury of rabbit limbs in early stage of high-voltage electrical burn.