弥漫性胰腺神经内分泌肿瘤的影像分析

Imaging analysis of diffuse pancreatic neuroendocrine tumors

目的:分析弥漫性胰腺神经内分泌肿瘤(pNET)的影像学表现,提高对该病诊断及鉴别诊断能力。方法:回顾性搜集2014年7月-2017年12月经病理证实的弥漫性pNET共9例的临床和影像学资料。所有患者均行胰腺增强CT检查,其中1例同时行MR检查。结果:本研究9例中8例为无功能pNET,激素指标均阴性,1例为胰高血糖素瘤,胰高血糖素升高。实验室检查中血尿淀粉酶及IgG4结果均阴性,肿瘤标志物有两例患者CA-199轻度升高,余肿瘤标志物检查均阴性。弥漫性pNET常见CT征象有强化不均匀(8/9),接触门静脉(8/9),淋巴结增大(7/9),接触动脉(6/9),边界清(6/9),动脉期明显或稍高强化(5/9),膨胀性生长(5/9)。结论:弥漫性pNET是少见疾病的罕见表现,典型的影像学表现为边界清晰,动脉期明显不均匀强化。其需与弥漫性胰腺癌、胰腺淋巴瘤、胰腺转移瘤及自身免疫性胰腺炎等鉴别。综合分析临床指标及CT征象有助于诊断及鉴别诊断。

Objective: To analyze the imaging features of diffuse pancreatic neuroendocrine tumors (pNET) and to improve its diagnosis and differential diagnosis performance. Methods: From July 2014 to December 2017,9 patients with pathologically diagnosed diffuse pNET were retrospectively enrolled.Their clinical and imaging data were collected.All patients underwent enhanced CT examination,and one of them underwent both CT and MR examination. Results: Of the 9 cases,eight patients were nonfunctional pNET,the hormone levels were normal,whileone patient was glucagonoma with elevated glucagon level.The results of blood and urine amylase and IgG4 were negative.Two patients had slight elevation of CA-199,and the rest were negative.The common CT signs of diffuse pNET included heterogeneous enhancement (8/9),portal vein involvement (8/9),lymph node enlargement (7/9),arterial involvement (6/9),clear margin (6/9),marked or slightly enhanced arterial phase (5/9),and expansive growth (5/9). Conclusions: Diffuse pNET is a rare manifestation of rare diseases.Its typical imaging features were clear boundary and markedly heterogeneous enhancement in arterial phase.It should be differentiated from diffuse pancreatic cancer,pancreatic lymphoma,pancreatic metastasis and autoimmune pancreatitis.Comprehensive analysis of clinical indicators and CT signs is helpful for diagnosis and differential diagnosis.