探讨合并肝硬化的小肝内胆管细胞癌（ICC）的MRI强化特征和鉴别诊断。

本前瞻性队列研究对象为2012年12月至2015年12月在第二军医大学附属东方肝胆外科医院接受外科手术治疗的56例合并肝硬化的小ICC患者。其中男40例，女16例；年龄29～74岁，中位年龄54岁。患者均签署知情同意书，符合医学伦理学规定。患者行肝脏动态增强MRI检查，静脉注射钆喷酸葡胺造影剂。增强MRI扫描包括肝动脉期、门静脉期和延迟期。采用kappa系数评估观察者间判读强化类型的一致性。强化类型与病灶直径相关性分析采用Fisher确切概率法。

观察者对病灶强化类型的判读一致性评价为优异（κ=0.82）。52% （29/56）小ICC表现为渐进型强化，36% （20/56）为稳定型强化，5%（3/56）为快进快出型强化，7%（4/56）为快进+衰退型强化。直径<20 mm病灶最常见的强化类型为稳定型强化，20～30 mm病灶最常见为渐进型强化，小ICC的强化类型与病灶直径具有相关性（P=0.006）。

合并肝硬化的小ICC强化类型主要为稳定型和渐进型，但少部分表现为快进快出的强化特征，此类型与小肝癌强化类似，为两者鉴别诊断的重点和难点。

To investigate the MRI enhancement features and differential diagnosis of small intrahepatic cholangiocarcinoma (ICC) combined with liver cirrhosis.

A total of 56 patients with small ICC combined with liver cirrhosis who underwent surgical treatment in the Eastern Hepatobiliary Surgery Hospital Affiliated to the Second Military Medical University between December 2012 and December 2015 were enrolled in this prospective cohort study. Among them, 40 cases were male and 16 were female, age 29-74 years old with a median age of 54 years old. The informed consents of all patients were obtained and the local ethical committee approval was received. All the patient underwent hepatic dynamic enhanced MRI examination and intravenous injection of Gd-DTPA contrast. The enhanced MRI imaging included hepatic arterial phase, portal vein phase and delayed phase. Inter-observer consistency of determining enhancement types was assessed by kappa coefficient. Correlation between enhancement type and lesion diameter was analyzed by Fisher's exact probability test.

The inter-observer consistency of determing lesion enhancement types was excellent (κ=0.82). 52%(29/56) of the patients with small ICC presented as progressive enhancement pattern, 36%(20/56) as stable pattern, 5%(3/56) as fast-in and fast-out pattern and 7%(4/56) as fast-in + recession pattern. The most common enhancement pattern for the lesions with a diameter of less than 20 mm was stable pattern, and progressive pattern for the lesions with a diameter of 20-30 mm. The enhancement pattern of small ICC was correlated with the diameter of lesion (P=0.006).

Most common MRI enhancement pattern for the patients with small ICC combined with liver cirrhosis are stable and progressive pattern. But some presents as fast-in and fast-out pattern, and this pattern is similar to that of small hepatocellular carcinoma, which is the key and difficult point for differential diagnosis between them.