胰腺肉瘤样癌的影像学特征

The Radiological Features of Sarcomatoid Carcinoma of Pancreas

目的探讨胰腺肉瘤样癌(SCP)的影像学表现。方法回顾性分析经手术病理证实的9例SCP的患者资料。其中6例患者行CT平扫及增强扫描,2例行MRI平扫及增强扫描,1例同时行CT、MRI检查,观察其影像学表现。结果9例均为单发病灶,7例肿瘤位于胰体、尾部,位于胰头部、胰颈部各1例。瘤体最大径1.9~9.8 cm。形态为类圆形6例,不规则形3例,2例边界清楚,7例边界不清。7例有囊变坏死,2例为实性病灶。CT平扫表现为低密度或稍低密度影,其中2例见出血密度影。MRI平扫表现为脂肪抑制T1WI呈低或稍低信号,脂肪抑制T2WI呈等或高信号;扩散加权成像(DWI)呈混杂高信号。增强扫描:动脉期均呈轻度或中度强化,随时间推移呈渐进性强化6例;门静脉期达强化峰值,延迟期强化退出2例;呈三期低强化1例。结论SCP体积较大,坏死囊变多见,强化方式与肿瘤的分化程度有关,呈"渐进性强化"或"门静脉期峰值强化"的特点。

Objective To investigate the radiological features of sarcomatoid carcinoma of pancreas.Methods A retrospective study was conducted on 9 patients with sarcomatoid carcinoma of pancreas confirmed by pathology.6 patients underwent CT plain and enhanced scan,2 patients underwent MRI plain and enhanced scan,while 1 patient underwent CT and MRI scan simultaneously,the CT and MR findings were analyzed.Results The lesion wassinglein all the 9 cases,7 cases were located in the body and(or)tail of pancreas,1 case in the head,1 case in the neck of the pancreas.The maximum diameter ranged from 1.9 to 9.8 cm.There were 6 round-like tumors,3 irregular tumors,and the margins of tumors were clear in 2 and unclear in 7 cases.7 cases had cystic and necrotic changes,while 2 cases were solid.On plain CT,the lesions showed low density or slightly low density,and hemorrhage could be detected in 2 lesions.On plain MRI,the lesions showed low or slightly hypointensityon T1WI with fat suppression,isointensity or hyperintensity on T2WI with fat suppression,and mixed high signalintensity on DWI.After enhancement,all the lesions showed mild or moderate enhancement in the arterial phase,progressive enhancement in 6 lesions,the enhancement was continued into the venousphases and decreased enhancement in delayed phases in 2 lesions;low enhancement in all the 3 phases in 1 lesion.Conclusion Sarcomatoid carcinoma of pancreas presented as alarge mass with necrosis and cystic changes.The pattern of the enhancement was related to the differentiation of the tumors,which was characterized by“progressive enhancement”or“peak enhancement in venous phases”.