Values Of Magnetic Resonance Diffusion-weighted Imaging On Prediction Of Radiosensitivity In Esophageal Carcinoma

Background and Objective: The radiosensitivity in the carcinoma is closely related to the effect of radiotherapy for esophageal carcinoma.If the radiosensitivity in the carcinoma can be monitored at early stage,which are valuable to the therapy plan confirming and adjusting.But,there is still no effective way to predict this radiosensitivity at present.The examination of DWI was a new functional iconography technology,some studies indicated that DWI scanning could be used to predict this radiosensitivity.This study intends to explore the predictive value of MR-DWI for detecting radiosensitivity in esophageal carcinoma,and to provide an experimental basis for its clinical application.Method: Patients with esophageal carcinoma were enrolled from March 2015 to January 2016,who received 3DCRT or IMRT treatment with or without chemotherapy.All of the patients accepted radiotherapy at the doses of 60 Gy,which was 2.0Gy each time,once a day,5 times/week,10 of them received concurrent chemotherapy of FP or TP.They all accepted the DWI examination before radiotherapy,two weeks after radiotherapy and at the end of radiotherapy.ADC values of esophageal primary tumor were measured before radiotherapy,two weeks after radiotherapy and at the end of radiotherapy.Therapeutic effect at the end of radiotherapy was assessed by short-term therapeutic effect evaluation criterion.By comparing and analysing the ADC values of pre-RT,two weeks after radiotherapy and post-RT,to find out its change rule and analyse the values of magnetic resonance diffusion-weighted imaging on prediction of radiosensitivity in esophageal carcinoma.Results:1.Based on the short-term therapeutic effect evaluation criterion of 1989 version,13 patients achieved complete remission（CR）after treatment（52.0%）,and 12 achieved partly remission（PR）（48.0%）.2.（1）.The ADC value of esophageal primary tumor before radiotherapy of the two were（1.61±0.63）×10^-3mm²/s and（1.42±0.33）×10^-3mm²/s,respectively.the ADC value of CR group was higher than that of PR group,however,no significant difference was found（t=0.995,P=0.333）.（2）.Two weeks after radiotherapy,The ADC value of the two were increased to（2.22±0.57）×10^-3mm²/s and（1.65±0.34）×10^-3mm²/s,respectively.the ADC value of CR group was higher than that of PR group,which were significantly different（t=3.033,P=0.007）,ROC（Receiver operating characteristic）analysis showed an AUC（Area Under the Curve）of 0.776 at an optimal cutoff value of 2.21×10^-3mm²/s.This allowed for a prediction of CR with a sensitivity of 61.5%,a specificity of 100%.（3）.After radiotherapy,The ADC value of the two were increased to（2.81±0.49）×10^-3mm²/s and（1.92±0.35）×10^-3mm²/s,respectively.The ADC value of CR group was higher than that of PR group,which were significantly different（t=5.238,P=0.000）,ROC analysis showed an AUC of 0.936 at an optimal cutoff value of 2.27×10^-3mm²/s.This allowed for a prediction of CR with a sensitivity of 92.3%,a specificity of 91.7%.3.（1）.The △ADC1 of the two were（0.60±0.21）×10^-3mm²/s and（0.24±0.16）×10^-3mm²/s,respectively.The △ADC1 of CR group was higher than that of PR group,which were significantly different（t=4.902,P=0.000）,ROC analysis showed an AUC of 0.929 at an optimal cutoff value of 0.41×10^-3mm²/s,This allowed for a prediction of CR with a sensitivity of 92.3%,a specificity of 83.3%.（2）.The △ADC2 of the two were（1.19±0.41）×10^-3mm²/s and（0.50±0.24）×10^-3mm²/s,the △ADC2 of CR group was higher than that of PR group,which were significantly different（t=5.173,P=0.000）,ROC analysis showed an AUC of 0.936 at an optimal cutoff value of 0.65×10^-3mm²/s.This allowed for a prediction of CR with a sensitivity of 100%,a specificity of 75.0%.4.（1）.The △ADC1% of the two were 45.26%±26.79% and 18.09%±13.49%,respectively.the △ADC1% of CR group was higher than that of PR group,which were significantly different（t=3.239,P=0.005）,ROC analysis showed an AUC of 0.833 at an optimal cutoff value of 25.08%.This allowed for a prediction of CR group with a sensitivity of 76.9%,a specificity of 75.0%.（2）.The △ADC2% of the two were 91.62%±55.17% and 38.56%±22.96%,respectively.The △ADC2% of CR group was higher than that of PR group,which were significantly different（t=3.182,P=0.006）,ROC analysis showed an AUC of 0.814 at an optimal cutoff value of 71.0%.This allowed for a prediction of CR with a sensitivity of 61.5%,a specificity of 91.7%.Conclusion: MR-DWI may be of great significance to predict the radiosensitivity in esophageal carcinoma.ADC value may be a quantitative indicator to predict the radiosensitivity in esophageal carcinoma.The ADC values of two weeks after radiotherapy and its change can predict the radiosensitivity and therapeutic effect in esophageal carcinoma at early stage.