Efficacy Analysis Of US-DOT And DCE-MRI In Predicting And Evaluating The Efficacy Of Neoadjuvant Chemotherapy For Breast Cancer

Objective Discuss the diagnostic value of quantitative parameters measured by ultrasound-guided diffuse optical tomography（US-DOT）in predicting and evaluating the efficacy of neoadjuvant chemotherapy（NAC）for breast cancer in the early stages,and compare the diagnostic value of US-DOT and dynamic contrast-enhanced magnetic resonance imaging（DCE-MRI）in evaluating the efficacy of NAC before and after treatment.The expectation is that US-DOT,as a non-invasive examination that can evaluate changes in blood supply within tumors,has similar diagnostic value to DCE-MRI in predicting and evaluating the efficacy of NAC on a molecular level.US-DOT can potentially replace DCE-MRI to some extent as an imaging technique for evaluating and monitoring the efficacy of NAC for breast cancer.Methods Select 44 patients diagnosed with primary breast cancer confirmed by histopathology at our Hospital from January 2020 to September 2022.According to the Response Evaluation Criteria in Solid Tumors（RECIST）1.1 standard,patients were classified into partial response（PR）group,complete response（CR）group,progressive disease（PD）group,and stable disease（SD）group.According to the Miller and Payne（MP）grading system,patients were divided into two groups,with MP grade G5 as the pathological complete response（p CR）group,and MP grades 1-4 as the non-p CR group.All patients underwent ultrasound-diffuse optical tomography（US-DOT）examination to obtain quantitative parameters of total hemoglobin concentration（HBT）,synthesis diagnostic index（SDI）,and tumor maximum diameter（d）before the first neoadjuvant chemotherapy（NAC）and before the third NAC.The differences in quantitative parameters between and within groups were analyzed,and the changes in HBT（ΔHBT）,SDI（ΔSDI）,and tumor maximum diameter（Δd）were calculated.The correlation between early changes inΔHBT,ΔSDI,andΔd was analyzed,and receiver operating characteristic（ROC）curves were drawn using postoperative pathology as the gold standard to analyze the cutoff values ofΔHBT,ΔSDI,andΔd for early prediction of good NAC efficacy（MP grades G4-G5）and p CR,and to calculate the diagnostic efficiency.All patients underwent dynamic contrast-enhanced magnetic resonance imaging（DCE-MRI）and US-DOT examination before the first NAC and before surgery to obtain quantitative parameters of volume transfer constant(K^trans),rate constant(K_ep),tumor maximum diameter（D）,HBT,SDI,and d.The differences in quantitative parameters between and within groups were analyzed,and changes inΔK^trans,ΔK_ep,ΔHBT,ΔSDI,Δd,andΔD before and after NAC were analyzed with DCE-MRI-derived D as the standard for tumor size.ROC curves were drawn using postoperative pathology as the gold standard to analyze the cutoff values ofΔK^trans,ΔK_ep,ΔHBT,ΔSDI,Δd,andΔD for predicting p CR after NAC and to calculate the diagnostic efficiency.The predictive value of early US-DOT examination for predicting NAC efficacy and the diagnostic value of changes in US-DOT and DCE-MRI parameters before and after NAC were analyzed.Results 1.According to the RECIST standard,there was no significant difference in the parameter values of K^trans,K_ep,D,HBT,SDI,and d among the CR group,PR group,and SD group before NAC,P values were 0.374,0.277,0.291,0.887,0.076 and 0.700 respectively.There were significant differences in the changes of△HBT,△SDI,and△d among the three groups after two cycles of NAC（P<0.05）,and among the three groups after NAC（P<0.05）.The values of K^trans,K_ep,D,HBT,and SDI decreased in different degrees before and after NAC,HBT,SDI,and K^trans,K_ep,D,HBT,SDI before and after NAC in each group（P<0.05）.The d values before and after NAC in the CR group and PR group decreased significantly（P<0.05）,but there was no significant difference in the SD group before and after NAC（P=0.121）.2.According to MP criteria,there were no statistically significant differences in K^trans,K_ep,HBT,and d values between the p CR and non-p CR groups before NAC treatment（P=0.177,0.150,0.579,0.191）,and the values of D and SDI were lower in the p CR group than in the non-p CR group,with statistically significant differences（P<0.05）.The differences in△HBT,△SDI,and△d between the p CR and non-p CR groups after two cycles of NAC treatment were statistically significant（P<0.05）.The△K^trans,△K_ep,△HBT,and△SDI after NAC treatment was greater in the p CR group than in the non-p CR group,with statistically significant differences（P<0.05）,while there was no statistically significant difference in△D and△d values between the two groups（D:P=0.227;d:P=0.127）.Within each group,there were statistically significant reductions in d,HBT,SDI,K^transand K_epduring the middle period of NAC treatment and before and after NAC treatment（P<0.05）.3.The correlation analysis showed that two cycles after NAC,△HBT and△d were positively correlated（r=0.399,P<0.05）,while there was no significant linear correlation between△SDI and△d（P=0.157）.Before and after NAC,△K^trans,△K_ep,△HBT,△d were positively correlated with the change in tumor maximum diameter△D,with correlation coefficients of 0.652,0.499,0.320,and 0.729,respectively（P<0.05）.However,there was no significant linear correlation between△SDI and the change in tumor maximum diameter（P=0.083）.4.ROC analysis showed that the cutoff value of△HBT for predicting good NAC response（G4-G5）after two cycles of NAC was 59.50μmol/L,with an AUC of 0.856,while the cutoff value for predicting p CR was 70.50μmol/L,with an AUC of 0.883.The cutoff value of△SDI for predicting good NAC response was 34.00,with an AUC of 0.753,while the cutoff value for predicting p CR was 46.00,with an AUC of 0.874.The cutoff value of△d for predicting good NAC response was 4.50mm,with an AUC of 0.738,while the cutoff value for predicting p CR was 6.50mm,with an AUC of 0.732.5.ROC analysis showed that before and after NAC,the cutoff value of△K^transfor predicting p CR was 1.67（min-1）,with an AUC of 0.819.The cutoff value of△K_epfor predicting p CR was 1.02%,with an AUC of 0.937.The cutoff value of△HBT for predicting p CR was 176.00μmol/L,with an AUC of 0.906.The cutoff value of△SDI for predicting p CR was 80.00,with an AUC of 0.753.The change in tumor size before and after NAC had no statistical significance in predicting p CR（△D:P=0.311,△d:P=0.099）.Conclusion 1.In the process of neoadjuvant chemotherapy（NAC）for breast cancer,the decrease in each parameter of ultrasound-detected tissue perfusion（US-DOT）and dynamic contrast-enhanced magnetic resonance imaging（DCE-MRI）is proportional to the effectiveness of NAC,indicating that both quantitative parameters of these two imaging modalities can predict and evaluate the effectiveness of NAC.2.The quantitative parameters of US-DOT can predict the pathological response to NAC early in the process,with clear predictive indicators and higher diagnostic performance,among which the functional indicators△HBT and△SDI have higher diagnostic performance than the morphological indicators△d.This indicates that changes in functional parameters within the tumour early in the NAC process are more predictive of NAC effectiveness than changes in tumour morphological parameters.3.The overall tumour maximum diameter measured by both imaging modalities after NAC is smaller than before NAC,but the△D and△d values measured before and after NAC cannot effectively evaluate the pathological response.4.The quantitative parameters of US-DOT and DCE-MRI before and after NAC can effectively evaluate the pathological response to NAC,with clear predictive indicators.Among these,the quantitative parameters△HBT of US-DOT and△K_ep,△K^transof DCE-MRI have no significant difference in diagnostic performance.This indicates that US-DOT can to some extent replace DCE-MRI to become an imaging modality for the evaluation and monitoring of NAC effectiveness for breast cancer.