胰腺实性假乳头状瘤的影像诊断

目的：分析胰腺实性假乳头状瘤（solid pseudopapillary tumor of pancreas，SPTP）的影像学特点，探讨影像学对于SPTP的术前诊断价值。方法回顾分析28例经手术病理检查证实的SPTP影像学资料（CT、MRI、PET-CT）。28例患者中，男6例，女22例；年龄12~72岁，平均34.6岁。CT增强扫描20例，MRI增强扫描12例，PET-CT扫描4例。结果25例肿瘤呈圆形或类圆形，边缘光滑，3例为不规则形，见深分叶征象。肿瘤表现为实性团块18例，囊实性肿块10例，5例伴钙化征象，CT增强扫描肿瘤实性部分或间隔呈渐进性轻至中度强化。磁共振信号欠均匀，实性部分T1WI呈等低信号，T2WI呈等高信号，囊性部分呈T1WI低信号，T2WI呈高信号，伴出血和钙化时信号变复杂。4例经18F-FDG PET-CT扫描患者，肿瘤的实性部分FDG摄取明显增高，最高达23.08。结论 SPTP的影像学表现具有一定的特征性，术前CT、MRI及PET-CT检查具有重要的诊断价值。

Objective To investigate analysis the imaging features and the preoperational diagnosis value of CT,MRI and PET-CT to solid pseudopapillary tumor of pancreas （SPTP）. Methods Imaging data of 28 cases with SPTP confirmed pathologically were analyzed retrospectively. The patients included 22 females and 6 males with mean age of 34.6 years （range 12-72）. 20 cases accepted CT scan,12 cases accepted MRI scan,and 4 cases accepted PET-CT scan. Results 25 lesions were round and oval in shape and 3 lesions were irregular,deep lobule sign were found. 18 tumors were displayed with solid tissue and 10 tumors were showed mixed density with solid and cystic. Calcification was found in 5 cases （5/28）. Mild to moderate enhancement gradually from arterial phase to venous phase were displayed both in solid ingredients and cystic interval on CT and MRI. MRI signal is uneven. The solid part of tumor was medium or low signal in T1WI,and medium or high signal in T2WI. While the cystic part was obviously lower signal in T1WI,and higher signal in T2WI. MRI signal became complex when SPTP accompanied with calcification and bleeding. 18F-FDG uptake of solid part of the tumor increased significantly in all 4 patients with PET-CT scan,and the maximum value was up to 23.8. Conclusions SPTP showed some specific characteristics on imaging,and preoperative CT,MRI and PET-CT played an important role on the diagnosis of SPTP.