磁共振扩散加权成像逐点分析法预测肝细胞癌射频消融治疗疗效的价值

Predictive value of diffusion-weighted imaging histogram in evaluation of the response to radiofrequency ablation in hepatocellular carcinoma

目的探讨肝细胞癌（HCC）射频消融（RFA）治疗前通过磁共振扩散加权成像（DWI）逐点分析法测得的表观扩散系数（ADC）值对其疗效的预测价值。方法选取经病理证实的73例单发病灶HCC患者，其中疾病稳定组35例，疾病进展组38例。在RFA治疗前对全部患者行屏气DWI扫描，使用DWI逐点分析法在病灶最大层面，测得最小10％ADC值（ADC10）、最小30％ADC值（ADC30）、最小50％ADC值（ADC50）以及平均ADC值（ADC100），并与非病变区域的ADC100对比，得到RADC10、RADC30、RADC50以及RADC100。结果RFA治疗前，疾病稳定组与疾病进展组患者的ADCmADC50、ADC100、RADC30、RADC50以及RADCl00的比较，差异均有统计学意义（均P〈0．05）。全组患者的无疾病进展生存时间（PFS）为（16．0±10．6）个月。Cox单因素分析结果显示，RADC10、RADC30、RADC50与全组患者的PFS有关（均P〈0．05）。Cox多因素分析结果显示，仅RADC50对全组患者的PFS有明显影响（P〈0．05）。以全组患者RADC50的中位数0．72为界，将患者分为两组，RADC50〈0．72组患者的PFS为（30．2±3．0）个月，RADC50≥0．72组患者的PFS为（20．0±3．1）个月，差异有统计学意义（P=0．01）。结论DWI逐点分析法测得的RADC50是预测HCC患者RFA治疗疗效的最稳定和关键因素。

Objective To evaluate the value of MR diffusion-weighted imaging （DWI） histogram analysis for predicting tumor progression in patients with hepatoeellular carcinoma （HCC） treated with radiofrequency ablation （RFA）. Methods In a retrospective study, both 35 stable patients and 38 progressive patients with biopsy-proven HCC underwent breath-hold DWI before RFA treatment. The pretreatment apparent diffusion coefficient （ADC） values were averaged from the lowest to 10th, 30th, 50th, and 100th percentile using DWI histogram analysis software respectively, and were called ADCI0, ADC30, ADC50 and ADC100. The ratios of ADC10, ADC30, ADC50 and ADC100 to mean ADC of non-lesional area were calculated, called RADC10, RADC30, RADC50 and RADC100, respectively. Results Before RFA treatment, the ADC30, ADC50, ADC100, RADC30, RADC50 and RADC100 values of the tumors in the progression group were significantly higher than those of the stable group （P 〈 0.05 for all）, respectively. The progression-free survival （PFS） of all patients was （16.0 ±10.6 ）months. Univariate Cox regression analysis indicated that RADClo, RADC30, RADCs0 values of the tumor were significantly associated with PFS （ P 〈0.05 for both）. In multivariate analysis, only the RADCs0 value of tumor was a significant predictor for tumor progression （ P 〈0.05 ）. When the cut-off value of RADCs0 （0.72） was used, the PFS of below the cut-off value group [ （ 30.2 ± 3.0 ） months ] was significantly higher than that of those above the cut-off value group [ （20.0 ±3.1） months] （P =0.01）. Conclusions Pre-RFA DWI histogram analysis may serve as a biomarker for predicting tumor progression in patients with HCC treated with RFA.