中文摘要：

目的 分析肝细胞癌（HCC）的表观扩散系数（ADC）值与组织学分化程度之间的关系,探讨ADC值评价HCC组织学分化程度的价值.方法 收集2006年8月至2013年12月中山大学第三附属医院病理证实的229例HCC患者,按照肿瘤分化程度分为3组,高分化组（34例）、中分化组（170例）、低分化组（25例）.所有患者均行MRI平扫、增强和DWI（1.5T,b值为0,600 s/mm2）检查,测量HCC的ADC值,并分析ADC值与组织学分化程度的关系.结果 高、中、低分化HCC的ADC值分别为（1.68 ±0.13）、（1.31±0.16）、（1.08±0.11）×10-3 mm2/s,低分化组低于中、高分化组,中分化组低于高分化组（均P ＜0.05）,HCC的ADC值与组织学分化程度呈显著正相关关系（r=0.693,P＜ 0.05）;ROC曲线分析显示ADC值用于诊断高分化HCC的最佳临界点为1.5×10-3 mm2/s,其敏感度和特异度分别为100％和94.36％;用于诊断低分化HCC的最佳临界点为1.235×10-3 mm2/s,其敏感度和特异度分别为73.5％和96％.结论 ADC值在预测HCC的组织学分化程度方面具有重要价值.

英文摘要：

Objective To determine the relationship between apparent diffusion coefficient （ADC） and histopathological differentiation of hepatocellular carcinoma （HCC）.Methods Magnetic resonance examinations of magnetic resonance imaging （MRI） plain scan,LAVA dynamic enhanced scan and diffusion weighted imaging （DWI） （1.5 T,b values：0 and 600 s/mm2） were retrospectively reviewed for 229 surgically resected HCCs.Histopathology revealed 34 well,170 moderately and 25 poorly-differentiated HCCs.The incidence of each ADC value was measured.The relationship between ADC and histopathological differentiation was also evaluated.Results The ADC value of well-differentiated HCCs （1.68 ± 0.13 × 10-3 mm2/s） was significantly higher those of moderately HCCs （1.31 ±0.16 × 10-3 mm2/s） （P ＜0.05） and poorly-differentiated HCCs （1.08 ± 0.11 × 10-3 mm2/s） （p ＜ 0.05）.There was a significant positive correlation between ADC value and differentiation of HCCs （r =0.693,P ＜ 0.05）.ROC analysis showed that the optimal cutoff point of ADC value was 1.500 × 10 3 mm2/s in diagnosing well-differentiated HCCs.A cutoff ADC value equal to or under 1.5 × 10-3 mm2/s was used to differentiate well-differentiated HCC from moderately and poorly-differentiated ones with a sensitivity of 100％ and a specificity of 94.36％.ROC analysis showed that the optimal cutoff point of ADC value was 1.235 × 10 3 mm2/s in diagnosing poorlydifferentiated HCCs.A cutoff ADC value equal to or above 1.235 × 10-3 mm2/s was used for differentiating poorly-differentiated HCC from well and moderately-differentiated ones with a sensitivity of 73.5％ and a specificity of 96％.Conclusion In clinical practice,ADC value is important for predicting histopathological differentiation of HCC and improving its diagnostic accuracy.