扩散加权成像在乳腺癌肝转移化学治疗效果早期评价中的应用

Application of DWI for assessing early treatment response of liver metastases from breast cancer to chemotherapy

目的探讨扩散加权成像(diffusion weighted imaging,DWI)对乳腺癌肝转移化学治疗效果的早期评价价值。方法选取23例乳腺癌肝内转移的患者,采用紫杉烷类(taxanes)进行化学治疗。于化学治疗前2天及化学治疗第3天、第28天分别行常规MRI平扫及DWI,并测定表观分布系数(apparent diffusion coefficient,ADC)。参照实体瘤疗效评价标准(response evaluation criteria in solid tumors,RECIST),依据化学治疗第28天较化学治疗前常规MRI检查肿瘤直径的变化划分为有效组与无效组。结果23例乳腺癌肝内转移患者中,共检出转移灶58个,其中有效组35个,无效组23个,有效组化学治疗前后ADC值分别为(0.93±0.16)×10-3 mm2/s,(0.81±0.14)×10-3 mm2/s,(1.21±0.13)×10-3 mm2/s;依据化学治疗第3天DWI检查测量ADC值,绘制ROC曲线,曲线下面积为0.79,其可信区间为65.2%~87.5%,取ADC=0.87×10-3 mm2/s作为判断化学治疗效果的临界点,具有较高的临床应用价值。结论化学治疗第3天的DWI检查ADC值可用于早期判断乳腺癌肝转移的化学治疗效果。

Objective To evaluate the application of diffusion weighted imaging(DWI)in predicting early response of liver metastases from breast cancer to chemotherapy.Methods Twenty-three patients with liver metastases from breast cancer were included.Chemotherapy regimen included taxanes.Routine plain MRI and diffusion-weighted imaging were obtained at 2 days before chemotherapy,3rd days and 28th day of chemotherapy,and apparent diffusion coefficient(ADC)values were measured.Lesions were divided into responder and non-responder group according to Response Evaluation Criteria In Solid Tumors(RECIST)based on routine MRI obtained before and at 28th day of chemotherapy.Results Fifty-eight lesions of 23 patients were identified,among which 35 lesions were responders and 23 lesions were non-responders.ADC values in responders before and after chemotherapy were(0.93±0.16)×10-3 mm2/s,(0.81±0.14)×10-3 mm2/s,(1.21±0.13)×10-3 mm2/s respectively.ROC curve of ADC value measured on DWI at 3rd days of chemotherapy was obtained,corresponding areas under the curve were 0.79 with a confidence interval of 65.2%~87.5%.A cutoff of ADC at 0.87×10-3 mm2/s was valuable in clinical application.ConclusionThe ADC values of DWI can predict the response of liver metastases from breast cancer at 3rd day of chemotherapy.