少见病理组织类型肝细胞癌的CT诊断

CT diagnosis of rare histological variant of hepatocellular carcinoma

目的探讨5种少见病理组织类型肝细胞癌的CT影像表现,进一步提高对肝细胞癌的认识。方法回顾性分析31例经手术病理证实的少见病理组织类型肝细胞癌的CT表现。结果透明细胞型肝细胞癌13例,其中3例平扫可见片状脂肪密度,所有CT增强均表现为"快进快出"。硬化型肝细胞癌4例,增强扫描动脉期呈不均匀、缓慢强化,门脉期及延迟期可见延迟强化。混合型9例,增强扫描动脉期5例可见强化,4例无明显强化。5例病灶部分延迟强化,4例无延迟强化。纤维板层型3例,动脉期明显强化,静脉期、延迟期缓慢消退,呈现"快进慢出"的CT增强表现,病灶中央瘢痕无强化。硬化型、混合型、纤维板层型cT平扫可见肝表面皱缩现象。致密型2例,CT平扫表现大部分坏死低密度灶,CT增强动脉期病灶周边可见强化,内大部分表现为类似于坏死无强化区。结论少见病理组织类型肝细胞癌的CT表现有一定的特征性。分析其CT平扫及增强表现特点,有助于此类型肝细胞癌的诊断。

Objective To explore and understand the CT findings of 5 rare histological variants of hepatocelhilar carcinoma. Methods CT findings of 31 cases of rare histological variants confirmed by surgery and pathology were analyzed retrospectively. Results 13 cases were clear cell hepatocellular carcinoma. 3 cases of them showed patchy fat density in plain scans. Enhanced CT showed features of ＂fast in fast out＂ which was similar to the common hepatocellular carcinoma. 4 cases belonged to sclerosis hepatocellular carcinoma. They appeared as heterogeneous, slowly enhancement on arterial phase images, and delay enhancement on portal venous phase and delay phase images. 9 cases belonged to mixed hepatocellular carcinoma. 5 cases of them showed inhomogeneous enhancement and 4 without enhancement during arterial phase, 3 cases showed delay enhancement and 4 without during portal venous and delay phase. 3 cases were fibrolamellar hepatocellular carcinoma. All showed obvious and fastly enhancement on arterial phase images, subsided slowly on the portal venous and delay phase images, showing features of ＂fast in slow out＂, no enhancement was seen in the central scar. Shrinkage phenomenon on the surface of liver could be seen on the CT plain scans in sclerosis, mixed and fibrolamellar hepatocelhilar carcinoma. 2 cases were the type of dense hepatocellular carcinoma. The surrounding part in the 2 cases were slightly enhanced, while the most part of the center were not enhanced similar to necrosis. Conclusion The CT findings of rare histological variant of hepatocellular carcinoma are characteristic. Analyzing the CT plain and enhancement finding is helpful to the diagnosis of these types of hepatocellular carcinoma.