中文摘要：

目的：探讨胰腺神经内分泌肿瘤（NETP）的CT、MRI、^18F-FDGPET/CT表现及其鉴别诊断价值。材料和方法：回顾性分析经手术病理证实的20例胰腺神经内分泌肿瘤（功能性7例,无功能性13例）的影像学资料,均行CT平扫及增强扫描,5例行MRI平扫及增强扫描,2例行PET/CT检查。结果：功能性NETP1例CT平扫、增强扫描及PET/CT均未显示;其余6例为等密度（5例）或略低密度（1例）;2例MRI均呈长T1长T2信号;动脉期（5例）或门静脉期（1例）明显增强,高于胰实质,且境界清楚。无功能NETP呈实性4例、囊实性7例、囊性2例;3例MRIT1WI呈低信号、T2WI呈高信号（2例）和稍高信号（1例）;1例PET/CT呈均匀高代谢的等密度结节;11例境界清晰;2例囊性肿瘤未见增强,实性和囊实性在动脉期（7例）或门静脉期（4例）显著增强,高于胰实质。结论：境界清晰和显著增强是胰腺神经内分泌肿瘤的CT、MRI特点,18F-FDGPET/CT对鉴别其性质有帮助。

英文摘要：

Purpose： In a group of neuroendocrine tumors of the pancreas （ NETP）, the value of CT.MRI and PET/CT in diagnosis and differentiation and the corresponding image characteristics were investigated. Materials and Methods： Imaging features in 20 patients with histopathologically proved NETP （7 functional and 13 nonfunctional tumors） were analyzed retrospectively. CT scan were performed in all patients, MRI and PET/CT were studied in 5 and 2 respectively. Results： Of 7 functional NETP, one lesion was missed by both CT and PET/CT, 5 cases was displayed as isodensity and one slightly low density in non-enhanced CT scan. MRI showed 2 cases of low signal intensity on T1WI and high signal intensity on T2WI. After contrast media injection, the lesions with clear border were more markedly enhanced than the pancreatic parenchyma in the arterial phase （5 cases） or in the venous phase （1 case） of CT and MRI. Of the 13 nonfunctional NETP, plain CT detected 4 solid masses, 7 cystic-solid masses and 2 cystic masses. MRI showed 3 cases with low signal intensity on T1WI, but 2 cases showed high signal intensity and one case slightly high signal intensity on T2WI. One case displayed a solid lesion with high radi- oactive accumulation by PET/CT. 2 cystic masses were not enhanced, others were more markedly enhanced than the pancreatic parenchyma in the arterial phase （7 cases） or in the venous phase （4 cases）. Conclusions： Clear border and marked enhancement of NETP are of characteristics in CT, MRI imaging. ^18F-FDG PET/CT is helpful in its differentiation.