Value of DWI for early assessment of response to concurrent chemoradiotherapy for esophageal cancer:a preliminary study / 中华放射肿瘤学杂志

ABSTRACT

Objective To investigate the feasibility and value of diffusion-weighted imaging (DWI) in the prediction and early assessment of response to concurrent chemoradiotherapy (CCRT) for esophageal cancer.Methods A total of 40 patients with pathologically confirmed esophageal cancer who received CCRT were included in the study.Routine 3.0 T MRI and DWI were performed at different time points of treatment.The RECIST standard was adopted to evaluate short-term outcomes and divide the patients into remission group (complete remission and partial remission) and non-remission group (stable disease and progressive disease).Group t-test was used for between-group comparison.The receiver operating characteristic (ROC) curve was used to analyze the change rates of apparent diffusion coefficient (ADC) value at different time points of treatment.Results There were 30 patients in the remission group and 10 patients in the non-remission group.The remission group had a significantly higher increase in ADC value than the non-remission group by the end of the first week of treatment (P =0.000).The maximum diameters of tumors for the emission group and non-remission group at the end of the first week of treatment were not significantly different from those before treatment (66.10 mm vs.62.63 mm,P =0.407 ; 70.90 mm vs.68.30 m,P =0.552).The ADC value before treatment had a negative correlation with the reduction rate of the maximum diameter of tumor (r =-0.680,P =0.000).The area under the ROC curve was the largest at the end of the first week of treatment (Az =0.783).If using 15.5 ％ increase in ADC value by the end of the first week as the threshold value for evaluating tumor response,the sensitivity,specificity,positive predictive value,and negative predictive value were 86.7％,70.0％,89.7％,and 63.6％,respectively.Conclusions DWI can be used as a new imaging method for the prediction and early assessment of the response to CCRT for esophageal cancer.The change rate of ADC value by the end of the first week of treatment is sensitive in assessing treatment response,so ADC value can be monitored at this time point.