Correlation Of Quantitative Parameters On Dynamic Contrast-Enhanced MRI With Pathological Grades Of Esophageal Squamous Cell Carcinoma

Background and purpose: Esophageal cancer is one of the common malignant gastrointestinal cancers in China.It ranks fifth in morbidity and fourth in mortality in China.The early symptoms of esophageal cancer are not obvious,and most clinical patients are in the middle and late stages.The overall 5-year survival rate is less than 20%.At present,the treatment of esophageal cancer at home and abroad is based on radical resection and supplemented with radiotherapy and chemotherapy.Therefore,it is of great significance to evaluate the early diagnosis of preoperative esophageal cancer,accurate preoperative staging,pathological grade,and evaluation of radiotherapy and chemotherapy.Dynamic contrast enhanced MRI(DCE-MRI)is a quantitative parameter functional imaging technique obtained by a hemodynamic model and can be used to evaluate the microcirculation of blood perfusion,vascular surface area,and vascular permeability of tissues.In the diagnosis of benign and malignant tumors,clear tumor grading,efficacy evaluation,tumor prognosis and recurrence in the diagnosis of important value.The results of the study show that high-resolution MRI has a good application value in the preoperative precise staging assessment of esophageal cancer.This study aims to investigate the application of DCE-MRI in the study of esophageal cancer to analyze the imaging features of esophageal cancer.Part1: Correlation of quantitative parameters on dynamic contrastenhanced MRI with pathological grades of esophageal squamous cell carcinomaObject: To investigate the correlation between DCE-MRI quantitative parameters and pathological grading in esophageal squamous cell carcinoma(ESCC).Methods: Prospective analysis of esophageal squamous cell carcinoma confirmed by electronic gastrointestinal endoscopy was performed.Thirty nine patients who underwent radical resection of esophageal carcinoma with MRI examination one weeks before operation were included.All patients underwent routine chest MRI and DCEMRI scans,and DCE-MRI quantitative parameters including volume transfer constant(Ktrans),exchange rate constant(Kep)and extravascular extracellular volume fraction(Ve)were measured.Pathological analysis of postoperative specimens,including pathological grading(highly differentiated,moderately differentiated,poorly differentiated,undifferentiated),gross tumor pathological type(ulcerative type,medullary type,fungating type,sclerotic type)and local infiltration degree(T staging)were performed.Kruskal-Wallis H test was used to compare the differences of quantitative parameters between different pathological T staging,gross tumor pathological types and pathological grades of DCE-MRI,and a Dunn Bonferroni test for post hoc comparisons.Spearman rank correlation analysis was used to evaluate the correlation between DCE-MRI parameters and pathological grading of esophageal squamous cell carcinoma.The ROC curves was used to evaluate the efficiency of different parameters in the diagnosis of poorly differentiated esophageal squamous cell carcinoma.Results: Among the thirty nine patients,they were divided into three group according to pathological findings: well differentiated(17 patients),moderately differentiated(29 patients)and poorly differentiated group(17 patients);ulcerative type(31 patients),fungating type(14 patients),medullary type(18 patients);T1,2 stage(27 patients),T3 stage(21 patients),and T4 stage(15 patients).There was no significant difference in the value of Ktrans,Kep and Ve between different T staging groups and different tumor pathological types groups(all P>0.05).The differences of Ktrans,Kep and Ve between different pathological grading groups were statistically significant(all P<0.05).There were positive correlation between Ktrans,Kep,Ve and the pathological grading,rs value were 0.816,0.646,0.504 respectively,all P<0.01.The ROC curve area of Ktrans,Kep and Ve in the diagnosis of poorly differentiated esophageal squamous cell carcinoma was 0.925,0.793 and 0.723 respectively.The diagnostic efficiency of Ktrans was the best.Conclusion: The quantitative parameters of DCE-MRI are correlated with the pathological grading of esophageal squamous cell carcinoma.Ktrans,Kep and Ve can reflect the perfusion characteristics of esophageal squamous cell carcinoma.Part2: Dynamic Contrast-Enhanced MRI in esophageal squamous cell carcinoma: Effects of Region of Interest Selection Methods on Measurement ReproducibilityObject: To investigate the influence of ROI on the measurement of quantitative parameters of dynamic contrast-enhanced MRI(DCE-MRI).Methods: Prospective collection of upper gastrointestinal endoscopy biopsy confirmed esophageal carcinoma,concurrent chest MRI examination within one week after radical esophagectomy 52 patients included in this study.Three different measures of ROI selection were used,including the whole-tumour ROI(ROIWT),the single-slice ROI(ROISS)and the hot-spot(ROIHS).The parameters of DCE-MRI were independently analyzed and measured by 2 radiologists.The parameters included volume transfusion constant(Ktrans),rate constant(Kep),and extravascular extracellular space volume ratio(Ve).Take the average of the results of Physician first as the final result of the observation.A paired t-test was used to assess intra-observer and interobserver differences.Intra-class correlation coefficient(ICC)and coefficient of variation(Co V)were used to assess the intra-observer and inter-observer repeatability.ANOVA test was used to compare the differences in parameters between different ROI methods.Results: The Ktrans,Kep,and Ve values obtained from the three different ROIs were highly consistent among intra-observer and inter-observer.The ROIWT method had the best agreement,with ICC values of 0.974 ~ 0.999,0.954 ~ 0.996 respectively.The Co V of Ktrans and Ve values measured by the ROIWT method was 1.45%,3.44%,and the interobserver Co V was 3.05%,4.34%,respectively,suggesting that the ROIWT method has good reproducibility.There was no significant difference between the intra-observer and the inter-observer in the quantitative parameters of three different ROI methods(P> 0.05).There was no significant difference in Kep and Ve between the three methods(P> 0.05).The Ktrans values measured by ROIHS method were higher than ROISS method(P <0.05).Conclusion: The results of three different ROI measurement methods showed better repeatability,but ROIWT was more suitable for the indirect evaluation of microcirculation of esophageal cancer using DCE-MRI.