胰腺实性假乳头状瘤CT和MRI表现及与组织病理学对照

CT and MRI manifestations of solid-pseudopapillary tumor of the pancreas:Compared with histopathological findings

目的探讨胰腺实性假乳头状瘤(SPT)的CT和MRI表现,并与手术和组织病理学比较。方法回顾性分析经组织病理学证实的16例胰腺SPT患者的CT和MRI表现,并与手术和组织病理学表现相比较。结果 16例胰腺SPT的CT和(或)MRI表现为实性肿块2例,囊实性肿块14例。2例呈分叶状和不完整包膜,1例界线不清,余13例呈轮廓规整的圆形,有完整包膜。增强后实性肿块和囊实性肿块实性成分动脉期或胰腺期呈轻度强化,门脉期呈渐进性强化。大体标本与CT表现具有较好一致性。组织病理学检查11例为良性,5例为低度恶性。有无包膜或包膜是否完整在良、恶性SPT间差异有统计学意义(P<0.05),而肿块大小和囊变程度在良、恶性SPT间差异无统计学意义(P>0.05)。结论胰腺SPT的CT和MRI特征表现为边界清晰的实性或囊实性肿块,增强后实性成分动脉期或胰腺期轻度强化,门脉期渐进性强化。包膜不完整或无明显包膜提示恶性可能。

Objective To observe CT and MRI features of solid-pseudopapillary tumor （SPT） of the pancreas, and to compare image findings with histopathological results. Methods CT and MRI findings of 16 patients with histopathologi- caly proved SPT were retrospectively analyzed, and compared with histopathological results. Results There were 2 pa- tients of solid masses and 14 patients with solid-cyst masses at CT and MRI. Tumors were lobulate and with discontinuous capsule in 2 patients, and without obvious capsule in 1 patient, while the remaining 13 tumors were round with complete capsule. After contrast media administration, the solid masses and solid-cyst masses demonstrated mild enhancement at the arterial or pancreatic phase and increasing enhancement at the portal venous phase. CT and MRI findings were in well ac- cordance with those of gross specimen. At histopathological examination, all 11 benign SPT and only 2 of 5 low-grade malignant SPT had obvious capsule （P〈0. 05）. There was no statistical difference between benign and malignant SPT in size and degree of cystic changes （P〉0.05）. Conclusion Characteristic manifestations of SPT of the pancreas at CT and MRI are of solid or solid-cyst masses with well demarcation and mild enhancement at the arterial or pancreatic phase, as well as progressive fill-in enhancement of the solid components at the portal venous phase. Discontinuous capsule or without obvious capsule may indicate the possibility of malignancy.