胰腺实性假乳头状肿瘤的影像学特征

The Imaging Characteristics of Solid Pseudopapillary Tumor of Pancreas

目的 回顾性分析实性假乳头状瘤(SPN)及假乳头状癌(SPC)的影像学特征。资料与方法搜集32例实性假乳头状肿瘤病例,其中SPC10例。32例中,男8例,女24例。10例SPC中,男3例,女7例。对SPN与SPC的一般特征及影像特征的差异作统计学分析,以P<0.05为有统计学意义。结果 22例SPN平均直径5.3cm。4例直径≤2cm的SPN表现为边界清晰、密度或信号均匀的肿物;13例直径≥5cm的SPN于CT上多表现为囊实性混杂密度(7/9),伴不同形态钙化(5/9)甚至液平面形成(1/9);于MRI上多信号混杂,表现为短T1的出血信号(4/5)。10例SPC平均直径6.4cm。8例位于胰头,1例位于胰体,1例位于胰尾。2例显著压迫邻近肠管,2例显著压迫下腔静脉及肠系膜静脉,余边界相对清晰。8例行CT检查的SPC中2例可见钙化。8例SPC出现胰管扩张,其中6例出现胆总管及肝内胆管扩张。3例SPC可见血管包绕:1例SPC包绕脾动脉,1例包绕门静脉,余1例包绕脾动静脉。统计学分析显示胆/胰管扩张和血管包绕在SPN与SPC的差别有统计学意义。结论 胰腺实性假乳头状肿瘤具有相对特异的影像特征,对符合影像特征且合并胰管、胆管扩张或血管包绕者,应诊断SPC。

Objective To retrospectively evaluate the imaging characteristics of solid pseudo-papillary neoplasm（SPN）and solid pseudo-papillary carcinoma（SPC）of pancreas.Materials and Methods Among 32 cases of pancreatic pseudopapillary tumor,10 tumors were SPC.There were 8 males with average age of 38 years old and 24 females with average age of 28 years old.Among 10 SPC cases,there are 3 males and 7 femaleThe average diameter of SPN was 5.3 cm.For 4 cases with diameter≤2 cm,the lesions showed as sharply-defined,homogeneous density or intensity mass.For 13 cases with diameter≥5 cm,most of them showed as inhomogeneous cystic-solid density（7/9）,different morphological calcification（5/9）and even fluid-debris level（1/9）on CT images;on MRI image,most of them were inhomogeneous intensity and showed short T1 signal indicating hemorrhage（4/5）.The average diameter of 10 SPC cases was 6.4 cm.Eight lesions were located in the pancreatic head and 1 in the body and 1 in the tail.The lesions had clear borders except for 2 lesions pressed the adjacent intestinal canal and 2 lesions obviously compressed the inferior vena cava and mesentery veins.Punctuate calcification were detected in 2 of the 8 cases.Pancreatic duct dilatation was seen in 8 SPC cases.Among them,common bile duct and intrahepatic bile duct dilatation was noted in 6 cases.Vascular embedment was seen in 3 SPC cases：spleen veins were involved in two cases and portal vein was involved in one case.There were significant differences of bile/pancreatic duct dialation and vessel embedment between SPN and SPC.Conclusion Solid pseudopapillary tumor had relatively specific imaging characteristics.For tumors involved pancreatic and/or bile duct or vascular embedment,the diagnosis of SPC should be made.