胰腺罕见肿瘤的影像学表现及误诊分析

Imaging findings and misdiagnosis analysis of rare pancreatic tumors

目的探讨几种胰腺罕见肿瘤的CT及MRI表现并分析其误诊原因,以提高其术前影像诊断率。方法回顾性分析经手术病理证实的8例胰腺罕见肿瘤的CT及MRI征象,结合相关文献进行综合分析。结果腺泡细胞癌2例,位于胰尾或胰体尾,均呈实性,增强实性成分呈渐进性强化,坏死区无强化;胶样癌1例,位于胰体尾,呈混杂稍低密度,内见团块状钙化,增强稍低密度区周边延迟强化;胰母细胞瘤1例,位于胰头,呈实性、分叶状,瘤内见淡薄斑片状钙化,增强实性成分不均匀轻度强化,囊变区无强化;嗜铬细胞瘤2例,1例位于胰头,呈囊性,囊液呈短T1短T2信号,囊壁明显强化,内壁不规则,1例位于胰颈,呈实性,增强各期明显强化,内见灶性坏死;间质瘤1例,位于胰头,呈实性,增强不均匀较明显强化。海绵状血管瘤1例,位于胰体,CT上边界欠清,不均匀轻度强化,T2WI呈明显高信号囊性肿块,边界清楚,增强肿瘤内部见絮状强化影。结论不同组织学类型的胰腺罕见肿瘤具有一定的影像学特征,综合CT及MRI表现可提高这些肿瘤的诊断准确性。

Objective To explore the CT and MRI findings of several rare pancreatic tumors and analyze the misdiagnosis causes to improve the diagnosis accuracy of the disease.Methods The CT and MRI features of 8 rare pancreatic tumors confirmed by operation and pathology were analyzed retrospectively,and relevant literatures were reviewed.Results 2 cases of acinar cell carcinoma located in the pancreatic body and tail were all solid.The solid components were gradually strengthened and the necrotic area was not strengthened.1 case of colloid carcino-ma was located in the pancreatic body and tail,with a mixed slightly low density,a lump calcification and periph-eral delay enhancement in the slightly low density area.1 case of pancreatoblastoma located in the head of the pan-creas was solid and lobulated,with thin and flaky calcification.The solid component was slightly heterogeneous en-hanced and the cystic area was not strengthened.Pheochromocytoma were 2 cases,and one case located in the head of the pancreas was cystic,the cystic fluid showed short T1 short T2 signal and the cystic wall was obviously strengthened,with the irregular inner wall.The other case was located in the pancreatic neck,and showed solid and intense enhancement in each phase,with focal necrosis.1 case of stromal tumors located in the head of pancre-as was solid,heterogeneously enhanced.1 case of cavernous hemangioma was located in the body of the pancreas.The tumor showed an unclear boundary,inhomogeneously mild enhancement on CT.T2WI showed an obvious high signal cystic mass with clear boundary and internal flocculation enhancement in the tumor.Conclusion The rare pancreatic tumors with different histological types have certain imaging characteristics.Combined CT and MRI find-ings can improve the diagnostic accuracy of these tumors.