胰腺实性-假乳头状瘤的多层螺旋CT诊断

Diagnosis of Solid-pseudopapillary Tumors of the Pancreas by Multi-detector Row Computed Tomography

目的:探讨胰腺实性-假乳头状瘤(SPTP)在多层螺旋CT上的影像特点。方法:回顾性分析40例经手术切除和病理学证实的胰腺实性-假乳头状瘤的临床、多层螺旋CT影像学资料,结合CTA、多平面重建和二维曲面重建等影像技术观察其影像学表现,分析影像学表现与病理结果的相关性。结果:女性35例,男性5例。40例患者SPTP影像学表现中,22例位于胰头,5例位于胰颈体交界区,6例位于胰体,3例位于胰体尾部,3例位于胰尾部,1例胰头、胰体尾部均见;类圆形30例,圆形5例,分叶状4例,表现为胰头增大1例,边界清楚,包膜完整;肿块多数较大,最大横断面达15 cm×18 cm,最小1.0 cm×1.1 cm;肿块完全实性7例,囊实性成分33例,其中囊性为主8例,实性为主17例,囊实性相仿8例。实性部分CT平扫呈稍低或等密度,增强扫描动脉期实性部分可见中等强化,至门静脉期肿瘤实性部分渐进性强化略高于动脉期,但强化程度均略低于正常胰腺组织,囊性部分平扫及增强均呈低密度。CT表现1例患者见恶性倾向,9例推压、包绕肠系膜血管,8例脾血管受压,3例累及肝总动脉及分支,2例累及十二指肠,11例伴有胰管扩张,其中1例伴有明显胆总管及肝内胆管扩张,13例伴有钙化。病理示良性37例,潜在恶性或低度恶性3例。结论:胰腺实性-假乳头状瘤具有特征性的影像学表现,螺旋CT能协助诊断,运用CTA、多平面重建和二维曲面重建等影像技术有助于术前评估肿瘤的良恶性。

Purpose： To evaluate the imaging features of solid-pseudopapillary tumors of the pancreas（SPTP） on multi-detector row computed tomography（MDCT）.Methods： A total of 40 patients with histopathologically confirmed SPTPs were included in this study.Axial MDCT images combined with CT angiography（CTA） and multiplanar volume reformations（MPVR） or curved reformations（CR） were preoperatively acquired.Results： Of the 40 patients,35 were females,5 were males.Among the total 40 patients with SPTPs on MDCT study,22 cases were located in the pancreatic head,5 cases were located in the pancreatic neck-body,6 cases were located in the pancreatic body,3 cases were located in the pancreatic body-tail,3 cases were located in the pancreatic tail,and 1 were both located in the pancreatic head and tail.The shapes of the tumors were circular in 30 cases,cyclograph in 5 cases,lobulated in 4 cases.The manifestation of one case of SPTP was enlargement of pancreatic head with clear boundary and intact capsule.Most tumors were bigger.The maximal diameters of the tumors were 15～18 cm,the minimum were 1.0～1.1 cm.Seven cases were shown as completely solid mass,33 cases were shown with cystic and solid components,of which 8 cases were with mainly cystic components,17 cases were with mainly solid components,8 cases were with almost the same amount of cystic and solid components.The solid portions were obviously enhanced in the arterial phase,and the density of them was slightly higher in portal venous phase on post-contrast CT,but lower than normal pancreas in both phases.One case was shown with malignant tendency on CT manifestations.Nine cases were shown that the mesenteric vascular compressive package was pushed,8 cases were shown that the spleen vascular was compressed,3 cases were shown that the liver common artery and branch were involved,2 cases were shown that the duodenum was involved,11 cases were shown with dilated pancreatic duct,1 case were shown with obvious common and intrahepatic bile duct dilation.Thirty cases of SPTPs were shown with calcification on CT.As the results of the histopathologic examination of the surgical specimen,37 of the 40 SPTPs were classified as adenomas,3 were classified as border line tumors and carcinomas.Conclusion： MDCT with CTA and MPVR or CR techniques is of great value in classifying and elucidating the imaging features of SPTPs.