磁共振扩散加权成像对肝细胞癌化疗栓塞术后疗效的随访价值

目的 探讨磁共振扩散加权成像（DWI）对肝细胞癌（HCC）经导管肝动脉化疗栓塞术（TACE）治疗后疗效评估的应用价值。方法 选取安徽省立医院2014年1月至2016年12月收治的经临床或病理检查确诊的52例HCC患者为研究对象,所有患者均经1～3次TACE治疗,并于TACE术前、术后4～6周行上腹部磁共振平扫及DWI检查,术后4个月行磁共振增强扫描,上述检查均在1周内完成。依据实体肿瘤疗效评估标准（mRECIST）,将病例分为稳定组和进展组,分析TACE术前、术后病灶的坏死、复发转移情况以及表观弥散系数（ADC）值;采用受试者工作特征曲线（ROC）确定鉴别稳定组和进展组的诊断效能以及ADC的最佳截断值。结果 52例HCC患者术前共计检出68个病灶;参照mRECIST标准,评价为稳定病例20例,进展病例32例。术前病灶以稍长T₁和T₂信号为主,DWI序列上呈高信号,ADC图上呈低信号;TACE术后,肿瘤坏死区呈等或稍长T₁、T₂信号,DWI序列上呈等或稍低信号。进展组于T₁WI和T₂WI序列上信号表现多样,DWI序列上呈不均性高信号;稳定组和进展组术前肿瘤病灶的ADC值差异无统计学意义（P>0.05）,稳定组术后ADC值较术前升高（P<0.05）,其手术前后ADC的增加值高于进展组（P<0.05）。ROC分析提示：鉴别稳定组和进展组ADC的最佳截断值为1.28×10^-3 mm²/s,此时曲线下面积为0.773（P<0.05）、灵敏度为76.3%、特异度为68.9%。结论 DWI扫描能够及时、客观的评估HCC患者化疗栓塞术后疗效,具有较高的随访价值。

Follow-up value of magnetic resonance diffusion weighted imaging in postoperative efficacy of chemoembolization in treatment of hepatocellular carcinoma

Objective To investigate the clinical application of magnetic resonance diffusion weighted imaging (DWI) to assess therapeutic efficacy for patients with hepatocellular carcinoma (HCC) treated by transcatheter arterial chemoembolization (TACE).Methods Fifty-two HCC patients with one to three times TACE treatments confirmed clinically or pathologically in our hospital from Jan 2014 to Dec 2016 were enrolled as subjects. All patients underwent plain-enhanced magnetic resonance imaging (MRI) and DWI scan before and four to six weeks after TACE, the contrast-enhanced MRI was performed four months after surgery, and all work was completed within one week. The cases were divided into stable group and progress group based on modified response evaluation criteria in solid tumors (mRECIST). The pre-TACE and post-TACE active components, necrosis, recurrence, metastasis and apparent diffusion coefficient (ADC) of HCC were qualitatively analyzed. The diagnostic value and the optimal cut off point of ADC in differentiating two groups were determined by receiver operating characteristic curve(ROC). Results A total of 68 lesions were found in 52 HCC patients before TACE, among which 20 cases were stable and 32 cases were advanced on the basis of the mRECIST. The main signal of HCC lesions was long T₁ and T₂ signal on DWI images and low signal on ADC maps before treatment; however, after TACE, the ischemic necrosis area of tumor presented equal or long signals on T₁WI and T₂WI with equal or low signal on DWI sequence, and the active lesion showed diverse signal on T₁WI and T₂WI as well as inhomogeneous high signal on DWI images. There was no significant difference in preoperative ADC value of tumor between the progress and stable groups (P>0.05); however, the postoperative ADC values of stable group were higher (P<0.05), which had a superior growth to progress group between before and after treatment (P<0.05). The result of ROC indicated that 1.28×10^-3 mm²/s was the cut off point of ADC in differentiating two groups with the 76.3% sensitivity, 68.9% specificity and 0.773 area under the curve (P<0.05). Conclusion DWI scan can predict the postoperative efficacy of HCC patients, which is of great application value for the further treatment plan.