胰腺导管内乳头状黏液性肿瘤恶变的影像表现

目的探讨胰腺导管内乳头状黏液性肿瘤(IPMN)恶变的影像表现和诊断价值。方法回顾分析经手术或超声内镜下活检病理证实的60例IPMN,探讨IPMN恶变的CT及MRI影像表现和诊断价值,并进行统计学分析。结果 60例患者共发现良性IPMN 34例,恶性26例。良性IPMNs的特征性表现为胰腺内囊性病灶,和主胰管相通,IPMNs恶变的特征有:增粗的胰管内出现明显强化的壁结节(17/26),结节直径>10 mm(13/26);主胰管直径>10 mm(10/26);或IPMN随访过程中出现胰腺明显肿块,胰管、胆管逐渐增粗、扩张加重。MRCP对IPMN与胰管相通的显示率高达91.7%(55/60),明显高于CT(76.7%,46/60)(χ²=5.065,P<0.05)。恶性IPMN中胆总管扩张有14例,而良性IPMN胆总管扩张仅2例。根据MRCP胆总管扩张情况诊断IPMN恶变的诊断敏感性及特异性分别为53.8%及94.1%,阳性预测值为87.5%。恶性IPMN DWI受限达21例(80.8%),良性IPMN DWI轻度受限5例(14.7%)。恶性IPMN的...

Imaging Features of Intraductal Malignant Papillary Mucinous Neoplasms of the Pancreas(IPMN)

Objective To investigate the CT and MRI imaging features and diagnostic value of malignant intraductal papillary mucinous neoplasms of the pancreas(IPMN).Methods Sixty patients with pathologically proved malignant IPMNs by surgery or biopsy who underwent MR imaging with MRCP and MDCT were retrospectively analyzed.There were 34 benign cases and 26 malignant or borderline cases.Results The characteristic manifestation of IPMN is that the cystic lesion communicates with the main pancreatic duct,while malignant IPMN features includes:intraductal enhancing solid components in a dilated pancreatic duct(17/26),the mucinous nodules>10 mm(13/26)and diameter of main duct>10 mm(10/26),or enlarged mass during the follow-up,the pancreatic duct and bile duct gradually dilated.MRCP showed the communication of IPMN with pancreatic duct in 91.7%cases which is higher than CT of 76.7%(χ^2=5.065,P<0.05).Bile duct dilation was seen in 14 malignant cases and in only 2 cases of benign cases.The sensitivity and specificity is 53.8%and 94.1%and positive predictive value is 87.5%.Restricted diffusion of malignant IPMN was present in 21 cases(80.8%)and only 5 cases(14.7%)in benign IPMN.The ADC value in malignant IPMN[(2.04±0.38)×10^-3mm^2/s]is lower than benign IPMN[(2.83±0.29)×10-3mm2/s].The area under ROC is 0.9383,the sensitivity and specificity is 80.8%and 94.1%with 2.34×10-3mm2/s as threshold and the 95%confidence interval is 80.32%-99.28%.The sensitivity of MRI and CT in diagnosis of malignant IPMN is 88.5%(23/26)and 80.8%(21/26);specificity is 88.2%(30/34)、79.4%(27/34)(P>0.05).Conclusion The MRI with MRCP and MDCT imaging demonstrate characteristics of IPMNs.Imaging is essential in establishing preoperative diagnosis and in evaluation of the malignant potential and resectability of IPMNs,which are of great aid in clinical plan and follow-up.