磁共振DWI图像在食管癌根治性放化疗疗效评价中的应用

Application of magnetic resonance DWI imaging in the evaluation of outcome of radical chemoradiotherapy for esophageal cancer

目的:探讨磁共振弥散加权成像(DWI)在食管癌患者根治性放化疗早期和远期疗效评价中的应用价值。方法:回顾性分析2013年10月至2017年6月在我院放疗科完成根治性同步放化疗的46例食管癌患者,所有患者在治疗前和治疗后1月行弥散加权成像,测量治疗前、治疗后病灶内表观弥散系数(ADCpre、ADCpost)和ADC变化值(△ADC,△ADC=ADCpost-ADCpre),实体瘤疗效评价标准评价放化疗疗效,应用ROC曲线分析各ADC值评价疗效的效能,并对患者长期随访,采用Kaplan-Meier曲线分析生存率。结果:治疗后1月进行疗效评价,33例有效,13例无效,治疗有效患者DWI图像高信号不同程度减退,甚至消失,治疗后ADC值明显高于治疗前ADC值。以治疗后ADC值和△ADC值为诊断食管癌放化疗早期疗效的ROC曲线下面积分别为0.795、0.841。随访后发现△ADC≥0.47×10-3mm2/s组的患者总生存率明显高于△ADC<0.47×10-3mm2/s组的患者,Log-rank法检验两组生存率有显著性差异。结论:DWI可以作为食管癌根治性放化疗早期疗效和远期生存的评价指标。

Objective:To evaluate the value of magnetic resonance diffusion-weighted imaging(DWI)in the evaluation of early and long-term outcome of radical chemoradiotherapy in patients with esophageal cancer.Methods:46 patients with esophageal cancer who completed radical chemoradiotherapy in our hospital from October 2013 to June 2017 were retrospectively analysed.DWI was performed in all patients before treatment and 1 month after treatment.Apparent diffusion coefficient(ADC)and changes in ADC(△ADC)inside lesions were measured before and after treatment,and the efficacy of chemoradiotherapy was evaluated by the criteria for evaluating the efficacy of chemoradiotherapy.ROC curve was used to analyze the efficacy of each ADC value.The patients were followed up for a long time,and the survival rate was analyzed by Kaplan-Meier curve.Results:The outcome was evaluated one month after treatment.33 cases were effective and 13 cases were ineffective.The high signal intensity of DWI images of patients with effective treatment decreased or even disappeared,and the ADC value after treatment was significantly higher than that of ADC before treatment.The areas under the ROC curve of ADC value and△ADC value after treatment for early efficacy of chemoradiotherapy for esophageal cancer were 0.795 and 0.841 respectively.After follow-up,it was found that the overall survival rate of patients with△ADC≥0.47×10-3 mm2/s was significantly higher than that of patients with△ADC<0.47×10-3 mm2/s.Log-rank test showed that there was a significant difference in survival between the two groups.Conclusion:DWI can be used as an index to evaluate the early efficacy and long-term survival of radical chemoradiotherapy for esophageal cancer.