Dynamic Contrast-enhanced MR Imaging For Advanced Esophageal Cancer Response Assessment And Progression-free Survival Prediction After Concurrent Chemoradiotherapy

PART One Dynamic contrast-enhanced MR imaging for advanced esophageal cancer response assessment after concurrent chemoradiotherapyObjectiveTo evaluate the treatment response of patients with esophageal cancer after concurrent chemoradiation therapy（CRT）by dynamic contrast-enhanced MR imaging（DCE-MRI）.MethodsThis retrospective study was enrolled 59 patients with histologically confirmed esophageal squamous cell carcinoma.The patients underwent DCE-MRI before and 4 weeks after CRT.The complete response（CR）patients were defined as the CR group;the partial response（PR）,stable disease（SD）,and progressive disease（PD）patients were defined as the non-CR group.DCE-MRI parameters(K^trans,V_e,and K_ep)were measured and compared between pre-and post-CRT in the CR and non-CR groups,respectively.Pre-CRT and post-CRT parameters were used to calculate change value（ΔX）and ratio（rΔX）.Comparisons of the DCE-MRI parameters were performed between the CR and non-CR groups.Receiver operating characteristic（ROC）curves were used to verify diagnostic performance.ResultsPatients with higher T-stage esophageal cancer might be presented with poorer response.After CRT,the K^trans and K_ep values significantly decreased in the CR group,whereas only K_ep value decreased in the non-CR group.The post-K^trans and post-K_ep values were observed to be significantly lower in the CR group than those in the non-CR group.The change values and ratios of K^trans and K_ep were all higher in the CR group than those in the non-CR group.Based on ROC analysis,rΔK^trans had the highest area under the curve of 0.840 in assessing response.ConclusionDCE-MRI parameters are valuable in assessing concurrent chemoradiation therapy response for advanced esophageal cancer.PART Two Histogram analysis of DCE-MRI for chemoradiotherapy response evaluation and prediction in locally advanced esophageal squamous cell carcinomaObjectivesThe mean or median markers of dynamic contrast-enhanced magnetic resonance imaging（DCE-MRI）in assessing chemoradiotherapy（CRT）response for patients with advanced esophageal squamous cell carcinoma may overlook tumor heterogeneity.Whole-lesion histogram-based analysis of DCE-MRI measurements can provide accurate markers to evaluate the heterogeneity of chemoradiotherapeutic response.Therefore,this study was to predict and assess treatment response using histogram analysis of DCE-MRI for patients with locally advanced esophageal squamous cell carcinoma receiving CRT.MethodsSeventy-two patients with locally advanced esophageal squamous cell carcinoma who underwent DCE-MRI before and after chemoradiotherapy were enrolled and divided into the complete response（CR）group（n=43）and the non-CR group（n=29）which are defined based on RECIST.Histogram parameters(10^th percentile,90^th percentile,median,mean,standard deviation,skewness and kurtosis)of pre-CRT and post-CRT were compared using paired student’s t test in the CR and non-CR groups respectively.Histogram parameter differences between the CR and non-CR group were compared by using unpaired student’s test.Receiver operating characteristic（ROC）analysis was performed to evaluate the diagnostic performance.ResultsThe median,mean,standard deviation,10^th and 90^th percentile of K^trans values were observed to be significantly decreased after chemoradiotherapy in the CR group.The CR responders showed significantly higher median,mean,10^th and 90^th percentile of pre-K^trans values than those of the non-CR group.Histogram analysis indicated decreased heterogeneity in the CR group after CRT.Esophageal cancer with higher pre-K^trans and lower post-K^trans values indicated good treatment response to CRT.Pre-K^trans-10^th showed the best diagnostic performance in predicting chemoradiotherapy response.ConclusionsHistogram parameters of K^trans are useful in chemoradiotherapy response predicting for patients with advanced esophageal squamous cell carcinoma.DCE-MRI could serve as an adjunctive imaging technique for treatment planning.PART Three Dynamic contrast-enhanced MRI histogram parameters predict progression-free survival in patients with advanced esophageal squamous carcinoma receiving concurrent chemoradiotherapyObjectivesTo explore whether histogram parameters derived from dynamic contrast-enhanced magnetic resonance imaging（DCE-MRI）can predict 12–month progression-free survival（PFS）in patients with advanced esophageal squamous carcinoma receiving concurrent chemoradiation therapy（CRT）.MethodsThis retrospective study was enrolled 134 patients with advanced esophageal squamous cell carcinoma receiving concurrent chemoradiotherapy.Pre-CRT DCE-MRI was undergone and histogram parameters(10^th percentile,90^th percentile,median,mean,standard deviation,skewness and kurtosis)of K^trans,K_ep and V_e were collected.The difference of demographic variables was performed between good and poor responders.PFS analyses were calculated using the Kaplan-Meier method and log-rank test to compute survival curves.The significant prognostic predictors of characteristic data and DCE-MRI histogram parameters were obtained using multivariate Cox proportional hazards regression analyses.ResultsThere were 65 patients in the good responders（PFS ≥ 12 months）and 69 patients in the poor responders（PFS < 12 months）.Significant difference in clinical T-stage,clinical N-stage,and CRT effect between good and poor responders was observed.The median and mean values of K^trans were higher and the kurtosis value of K^trans was lower in the good responders than those in the poor responders.The median,mean,10^th and 90^th percentages values of K^trans were higher and the kurtosis values of K^trans and V_e were lower in the good responders than those in the poor responders.The PFS time of patients with age≥60 years,or CR effect,or 10^th percentile value of K^trans≥0.13 was longer（P value was <0.001,<0.001 and 0.014,respectively）.ConclusionsDCE-MRI histogram parameters can be used in evaluating the response to concurrent chemoradiation therapy in patients with advanced esophageal squamous carcinoma.The 10^th percentile value of K^trans has significant prognostic value for the 12-month progression-free survival.