Objective To investigate the predictive value of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)radiomics combined with Magee equation 3(ME3)for pathological response following neoadjuvant chemotherapy(NAC)in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative(HR+/HER2-)breast cancer.Methods A ret-rospective analysis was performed on 325 breast cancer patients diagnosed with HR+/HER2-in two hospitals.Patients from the first hospital were randomly divided into training and internal validation sets at a ratio of 7∶3.Patients from the second hospital served as external validation set.The volume of interest(VOI)of breast cancer was delineated on DCE-MRI images.Then the rele-vant radiomics features were extracted and selected,and the Radiomics score(Radscore)was calculated.The statistically significant clinical and pathological features and Radscore were incorporated into a multivariate analysis.The combined radiomics-clinical model and nomogram were established,and the prediction performance was evaluated by using the receiver operating characteristic(ROC)curve,calibration curve,and decision curve analysis(DCA).Results In the training set,seven radiomics features were selected to construct the radiomics model.ME3 score emerged as the independent factor for pathological complete response(pCR)(P＜0.001).By integrating ME3 score and Radscore,a combined radiomics-clinical model was developed.This model demonstrated robust predictive accuracy,with area under the curve(AUC)of 0.88[95％confidence interval(CI)0.80-0.95],0.90(95％CI 0.82-0.98),and 0.82(95％CI 0.70-0.93)in the training,internal validation,and external validation sets,respectively.The nomogram construc-ted from the combined model exhibited excellent discrimination and calibration,with P-values of 0.455,0.312 and 0.062 in the train-ing,internal validation,and external validation sets.Conclusion DCE-MRI radiomics combined with ME3 can be used to predict the pathological response of NAC in HR+/HER2-breast cancer.

Objective To investigate the predictive value of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)radiomics combined with Magee equation 3(ME3)for pathological response following neoadjuvant chemotherapy(NAC)in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative(HR+/HER2-)breast cancer.Methods A ret-rospective analysis was performed on 325 breast cancer patients diagnosed with HR+/HER2-in two hospitals.Patients from the first hospital were randomly divided into training and internal validation sets at a ratio of 7∶3.Patients from the second hospital served as external validation set.The volume of interest(VOI)of breast cancer was delineated on DCE-MRI images.Then the rele-vant radiomics features were extracted and selected,and the Radiomics score(Radscore)was calculated.The statistically significant clinical and pathological features and Radscore were incorporated into a multivariate analysis.The combined radiomics-clinical model and nomogram were established,and the prediction performance was evaluated by using the receiver operating characteristic(ROC)curve,calibration curve,and decision curve analysis(DCA).Results In the training set,seven radiomics features were selected to construct the radiomics model.ME3 score emerged as the independent factor for pathological complete response(pCR)(P＜0.001).By integrating ME3 score and Radscore,a combined radiomics-clinical model was developed.This model demonstrated robust predictive accuracy,with area under the curve(AUC)of 0.88[95％confidence interval(CI)0.80-0.95],0.90(95％CI 0.82-0.98),and 0.82(95％CI 0.70-0.93)in the training,internal validation,and external validation sets,respectively.The nomogram construc-ted from the combined model exhibited excellent discrimination and calibration,with P-values of 0.455,0.312 and 0.062 in the train-ing,internal validation,and external validation sets.Conclusion DCE-MRI radiomics combined with ME3 can be used to predict the pathological response of NAC in HR+/HER2-breast cancer.

BACKGROUND: It is of great importance in improving the clinical effect of human islet allograft to study and design models of such large animals as pigs or primates preclinically.OBJECTIVE: To evaluate the effect of different doses of streptozotocin (STZ) on inducing diabetes type Ⅰ models of nonhuman primates.DESIGN, TIME AND SETTING: A contrast observational animal experiment was performed in the Cell Transplantation and Gene Therapy Center, the Third Xiangya Hospital of Central South University from October 2007 to December 2008. MATERIALS: A total of 21 adult male rhesus monkeys were divided into a 125 mg/kg STZ group (n =5), a 75 mg/kg STZ group (n=5) and a 50 mg/kg STZ group (n=11).METHODS: STZ weighed with regard to body mass of animals was prepared into 25 g/L STZ solution with buffer that was prepared in advance. After being filtered and degermed, the new-prepared STZ of 125 mg/kg, 75 mg/kg and 50 mg/kg were administered by intravenous injection into the experimental monkeys respectively, which took 1-5 minutes.MAIN OUTCOME MEASURES: Liver and renal function, glucose metabolism and histomorphological changes of animals during 1-16 weeks following administration.RESULTS: In 125 mg/kg STZ group, two rhesus monkeys died, in 8 hours following STZ administration, of serious hypoglycemia caused by severely damaged pancreas β cells; All rhesus monkeys in this group had got significantly increased liver transaminase, serum creatinine and urea nitrogen at week 1 following STZ administration, which reached a peak during 2-4 weeks; One rhesus monkey in this group showed severe shortage of endogenous trypsin and hyperglycemia irreversible by exogenous insulin following STZ administration, and finally died at day 13 following STZ administration due to the glucose metabolic disorder, ketoacidosis, liver and renal failure; The other two survivors in this group kept high level of liver transaminase,urea nitrogen and serum creatinine throughout the observation period. In 75 mg/kg STZ group, rhesus monkeys presented significantly increased liver transaminase, serum creatinine and urea nitrogen at week 1-2 following STZ administration; After 4 weeks following administration, their liver and renal function presented with abnormality of different degrees; One rhesus monkey in this group had got injured renal function, decreased power of resistance, eyelid edema, general dropsy and irreversible infected rump after injection of STZ, and finally died at the end of week 5 following administration; Another rhesus in this group presented with irreversible continuous hyperglycemia, inappetence and significantly decreased weight, and finally died ofsystemic failure at week 9 following administration. In the 50 mg/kg STZ group, renal function of monkeys were slightly affected, with a transient mild rise which return to the normal level by the end of week 4 following administration; Only 3 animals in this group appeared eyelid edema during 1-4 weeks following administration which disappeared afterwards.CONCLUSION: STZ of 50 mg/kg is possibly the optimal dose for inducing diabetes models in most rhesus monkeys.