伴有胰管梗阻的胰腺神经内分泌肿瘤影像学表现及误诊原因分析

目的：分析伴有胰管梗阻的胰腺神经内分泌肿瘤（pNENs）的影像特征及误诊情况。方法：回顾性分析25例伴有胰管梗阻的pNENs，由2名高年资影像诊断医师统计资料并总结其影像学表现及误诊原因。结果： 25名患者共26个病灶纳入研究，包括G1级病灶6例，G2级19例，G3级1例，病灶平均大小为2.5±1.7cm（0.4—9.1cm）。主胰管轻度扩张12例（46.2%），中度扩张8例（30.8%），显著扩张6例（23.1%）。17例（65.4%）病灶上游胰腺实质重度萎缩，6例（23.1%）上游胰腺实质中度萎缩，1例（3.8%）上游胰腺实质轻度萎缩，2例（7.7%）肿瘤上游胰腺实质未见萎缩。术前26个病灶14例（53.8%）正确诊断为pNENs，8例（30.8%）误诊为胰腺癌，2例（7.7%）误诊为胰腺实性假乳头状瘤，1例（3.8%）误诊为胰腺导管内乳头状粘液瘤，1例（3.8%）误诊为胰腺浆液性囊腺瘤。误诊原因主要为：病灶表现不典型，对疾病的不典型表现认识不足，影像细节观察不到位，未完整结合患者临床资料。结论：伴有胰管梗阻的pNENs有时与其它胰腺肿瘤的鉴别诊断存在难度，熟悉该病不典型表现、细心观察影像细节同时密切结合临床症状分析有助于减少误诊，提高该病的诊断正确率。

Imaging feature and misdiagnosis reason of pancreatic neuroendocrine neoplasm with pancreatic duct obstruction

Objective: to analyze the imaging features and misdiagnosis of pancreatic neuroendocrine tumors (pNENs) with pancreatic duct obstruction.Methods: Twenty-five cases of pNENs with pancreatic duct obstruction were analyzed retrospectively. The imaging manifestations and misdiagnosis reasons of pNENs were summarized by 2 experienced radiologists.Results: A total of 26 lesions were included in the study, including 6 G1 tumors, 19 G2 tumors and 1 G3 tumor. The average size of the lesions was 2.5 ± 1.7cm (0.4-9.1cm). The main pancreatic duct was slightly dilated in 12 cases (46.2%), moderately dilated in 8 cases (30.8%), and marked dilated in 6 cases (23.1%). Seventeen cases (65.4%) were with marked upstream pancreatic atrophy, 6 cases (23.1%) were with moderate upstream pancreatic atrophy, 1 case (3.8%) was with minimal upstream pancreatic atrophy, and 2 cases (7.7%) showed no upstream pancreatic atrophy. Fourteen (53.8%) of 26 lesions were correctly diagnosed as pNENs, 8 (30.8%) lesions were wrongly diagnosed as pancreatic cancer, 2 (7.7%) as solid pseudopapillary tumors, 1 (3.8%) as intraductal papillary mucinous neoplasm and 1 (3.8%) as serous cystadenoma. The main causes of misdiagnosis are: atypical lesions, lack of understanding of the atypical manifestations of the disease, inadequate observation of image details, and incomplete combination of clinical data.Conclusion: Sometimes it is difficult to differentiate pNENs with pancreatic duct obstruction from other pancreatic tumors. Being familiar with the atypical manifestations of the disease, observing the image details carefully and combining clinical data with imaging findings will be helpful to reduce misdiagnosis and improve the accuracy of diagnosis.