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71.
目的探讨胰腺导管内乳头状黏液性肿瘤在多层螺旋CT上的影像特点。方法回顾性分析30例经手术切除和病理学证实的胰腺导管内乳头状黏液性肿瘤的临床、多层螺旋CT影像学资料,结合CT血管造影(computed tomography angiography,CTA)、多平面图像重组和二维曲面重组等影像技术观察其影像学表现,分析影像学表现与病理结果的相关性。结果 30例胰腺导管内乳头状黏液性肿瘤的多层螺旋CT诊断:主胰管型13例,分支胰管型9例,混合型8例;术后病理结果显示胰腺导管内乳头状黏液性瘤8例,胰腺交界性或低度恶性乳头状黏液瘤8例,胰腺导管内乳头状黏液癌14例。结论胰腺导管内乳头状黏液性肿瘤具有特征性的影像学表现,螺旋CT能协助诊断并能对其分型,运用CTA、多平面图像重组和二维曲面重组等影像技术有助于术前评估肿瘤的良、恶性。  相似文献   
72.
目的:探讨胰腺导管内乳头状黏液性肿瘤(intraductal papillary mucinous neoplasm,IPMN)相关浸润性癌患者的临床病理特征及预后特点。方法:回顾性分析52例胰腺IPMN相关浸润性癌患者的临床资料和病理学特征,并随访其生存情况。结果:52例患者的中位发病年龄为65岁;36例患者的肿瘤发生在胰头部,15例发生在胰体尾部,1例为全胰导管内均有病变。IPMN类型包括,23例胃型,12例肠型,9例胆胰型,7例混合型(“胃型”+“胆胰型”),1例嗜酸细胞型;浸润性癌类型包括37例导管腺癌,13例胶样癌,1例未分化癌和1例腺鳞癌。血清CA19-9升高的情况在导管腺癌患者中更为显著,浸润性癌类型为导管腺癌患者的CA19-9阳性率为67.57%(25/37),而浸润型癌类型为胶样癌的患者中CA19-9阳性率为30.77%(4/13)。43例获得随访资料的患者中,无淋巴结转移的患者共30例,中位生存时间较13例淋巴结转移患者(39个月比13个月)长,差异有统计学意义(P<0.05);肿瘤局限于胰腺内的21例患者,其中位生存时间较肿瘤浸润胰腺外的22例患者长(45个月比24个月),差异有统计学意义(P<0.05)。43例患者获得随访,中位随访时间为16个月(5~57个月),其中1例复发,17例死亡。结论:胰腺IPMN相关浸润性癌类型以导管腺癌为主,而血清CA19-9升高与浸润性癌类型相关。淋巴结转移及肿瘤胰腺外侵犯是胰腺IPMN相关浸润性癌患者预后不良的危险因素。  相似文献   
73.
Pancreatic cystic lesions (PCLs) are becoming more prevalent due to more frequent abdominal imaging and the increasing age of the general population. It has become crucial to identify these PCLs and subsequently risk stratify them to guide management. Given the high morbidity associated with pancreatic surgery, only those PCLs at high risk for malignancy should undergo such treatment. However, current diagnostic testing is suboptimal at accurately diagnosing and risk stratifying PCLs. Therefore, research has focused on developing new techniques for differentiating mucinous from non-mucinous PCLs and identifying high risk lesions for malignancy. Cross sectional imaging radiomics can potentially improve the predictive accuracy of primary risk stratification of PCLs at the time of detection to guide invasive testing. While cyst fluid glucose has reemerged as a potential biomarker, cyst fluid molecular markers have improved accuracy for identifying specific types of PCLs. Endoscopic ultrasound guided approaches such as confocal laser endomicroscopy and through the needle microforceps biopsy have shown a good correlation with histopathological findings and are evolving techniques for identifying and risk stratifying PCLs. While most of these recent diagnostics are only practiced at selective tertiary care centers, they hold a promise that management of PCLs will only get better in the future.  相似文献   
74.
The differential diagnosis between benign and malignant biliary strictures is challenging and requires a multidisciplinary approach with the use of serum biomarkers, imaging techniques, and several modalities of endoscopic or percutaneous tissue sampling. The diagnosis of biliary strictures consists of laboratory markers, and invasive and non-invasive imaging examinations such as computed tomography (CT), contrast-enhanced magnetic resonance cholangiopancreatography, and endoscopic ultrasonography (EUS). Nevertheless, invasive imaging modalities combined with tissue sampling are usually required to confirm the diagnosis of suspected malignant biliary strictures, while pathological diagnosis is mandatory to decide the optimal therapeutic strategy. Although EUS-guided fine-needle aspiration biopsy is currently the standard procedure for tissue sampling of solid pancreatic mass lesions, its diagnostic value in intraductal infiltrating type of cholangiocarcinoma remains limited. Moreover, the “endobiliary approach” using novel slim biopsy forceps, transpapillary and percutaneous cholangioscopy, and intraductal ultrasound-guided biopsy, is gaining ground on traditional endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography endobiliary forceps biopsy. This review focuses on the available endobiliary techniques currently used to perform biliary strictures biopsy, comparing the diagnostic performance of endoscopic and percutaneous approaches.  相似文献   
75.
This report describes serial observations of the growth process of a small invasive ductal carcinoma (IDC) of the pancreas from imaging studies. Histopathological studies showed IDC with macroscopic retention cysts proximal to an intraductal papillary-mucinous adenoma with mild atypia of the branch duct type in the pancreatic body, with no relation between the two lesions. IDC was demonstrated as an extremely low-echoic mass resembling a cyst with an unclear margin on the initial endoscopic ultrasonography. We misinterpreted the lowechoic mass as a benign intraductal mucinous-papillary neoplasm (IPMN) based on findings of other imaging studies, and the patient was followed-up. The mass increased from 7 mm to 13 mm in diameter over 22 mo, and remained smaller than 10 mm in diameter for about 420 d. The tumor volume doubling time was 252 d. The Ki67 labeling index was 15.9%, similar to that described in previous reports. Hence, IDC may grow slowly while remaining small.  相似文献   
76.
Intraductal endoscopy describes the use of an endoscope to directly visualize the biliary and pancreatic ducts. For many years, technological challenges have made performing these procedures difficult. The “mother-baby” system and other various miniscopes have been developed, but routine use has been hampered due to complex setup, scope fragility and the time consuming, technically demanding nature of the procedure. Recently, the SpyGlass peroral cholangiopancreatoscopy system has shown early success at providing diagnostic information and therapeutic options. The clinical utility of intraductal endoscopy is broad. It allows better differentiation between benign and malignant processes by allowing direct visualization and targeted sampling of tissue. Therapeutic interventions, such as electrohydraulic lithotripsy (EHL), laser lithotripsy, photodynamic therapy, and argon plasma coagulation (APC), may also be performed as part of intraductal endoscopy. Intraductal endoscopy significantly increases the diagnostic and therapeutic yield of standard endoscopic retrograde cholangiography (ERCP), and as technology progresses, it is likely that its utilization will only increase. In this review of intraductal endoscopy, we describe in detail the various endoscopic platforms and their diagnostic and clinical applications.  相似文献   
77.
Pancreatic cancer (PC) continues to have a very poor prognosis. New epidemiological trials suggest that statins could play a protective role in smokers, while HbsAg-positive hepatitis B virus could be a risk factor. Endoscopic ultrasound (EUS) is the main diagnostic tool for PC, and new technologies associated with this technique have emerged, such as quantitative elastography, intravenous contrasts or, more recently, LASER confocal endomicroscopy. New markers in urine or pancreatic juice have appeared to distinguish between PC and chronic pancreatitis. The role of the “on site” cytopathologist to increase the diagnostic yield of EUS-guided pancreatic sampling is completely supported by new prospective trials and some multicenter studies have been reported that compare the standard cytologic needles with the new procore-histology needles. Regarding cystic pancreatic tumors, most studies have aimed to validate the 2012 Sendai international guidelines and to ascertain predictive factors of malignancy in cystic lesions, mainly intraductal papillary mucinous neoplasm (IPMN). The role of intracystic CEA levels in determining malignancy is challenged. From a therapeutic point of view, EUS-guided radiofrequency ablation of cystic and solid lesions has emerged as a feasible and safe procedure in specific circumstances.  相似文献   
78.
Intraductal papillary mucinous neoplasm (IPMN) is an increasingly reported entity. Extensive pancreatic calcification is generally thought to be a sign of chronic pancreatitis, but it may occur simultaneously with IPMN leading to diagnostic difficulties. We report a case of a patient initially diagnosed with chronic calcifying pancreatitis who was later shown to have a malignant IPMN. This case illustrates potential pitfalls in the diagnosis of IPMN in the case of extensive pancreatic calcification as well as clues that may lead the clinician to suspecting the diagnosis. The possible mechanisms of the relation between pancreatic calcification and IPMN are also reviewed.  相似文献   
79.
Background: This is the first study to correlate intraductal ultrasonography (IDUS) with cholangioscopy in evaluating the patency of biliary metallic stents. Methods: The findings of IDUS (probe 2.0 mm in diameter and 20-MHz frequency) through a percutaneous transhepatic (n = 24) or transpapillary (n = 2) approach were retrospectively reviewed without other information. Criteria for IDUS are as follows: type 1, the inside of the stent is free; type 2, the inner edge is smooth; type 3, the inner edge is irregular; type 4, the inside of the stent is totally occupied; type 5, the solid echo is connected to the outside mass; type 2+D, a hypoechoic line is seen between the bile duct wall and the inside solid component and the inner edge of the bile duct wall is smooth; type 3+D, an irregular hypoechoic line is seen between the bile duct wall and the inside solid component. Results: In the control group (n = 11), IDUS showed type 1 (n = 9) or type 2 (n = 2). In the occluded group (n = 15), when IDUS showed type 3 or 5, the patients (n= 5) required additional stents (n = 3), microwave coagulation of the tumor (n= 1), or transient external drainage (n= 1). When IDUS showed type 4 (n = 5), after washing, the findings changed to type 2+D (n = 4). When IDUS after washing showed a smooth inner edge (type 2+D), the patients were treated without additional stents more frequently than the other groups (eight of nine vs. two of six), a significant distinction (p < 0.05). Conclusion: IDUS is useful in assessing the patency of metallic stents. When the inside of the stent is totally occupied, however, examination after washing is necessary. Received: 19 May 2000/Accepted: 28 June 2000  相似文献   
80.
《Pancreatology》2016,16(3):416-422
Background/ObjectivesIn absence of evidence-based guidelines of pancreatic cystic neoplasms (PCN), the management might vary among physicians. The aim of this survey was to assess the attitude of Dutch gastroenterologists (GE) towards the management of asymptomatic PCNs.MethodsAn anonymous online questionnaire was distributed to all practicing GE (n = 381) in The Netherlands, in which four vignette patients with PCN were presented.ResultsIn total 45% of GE responded. Most respondents would perform surveillance for a 10 mm PCN (78%) mainly with an interval of one year (57%). A shorter interval of three (26%) or six (57%) months was chosen for a 25 mm BD-IPMN. Ultrasound was recommended for surveillance by 19% for a 10 mm cyst. GE with EUS experience were more likely to apply EUS for surveillance of 10 mm cyst than those without (56% vs 28%; p < 0.001). The presence of a branch-duct intraductal mucinous neoplasm (BD-IPMN) with a mural nodule, dilated pancreatic duct (8 mm) or increased serum CA 19.9 (300 U/ml) were considered an indication for resection by respectively 88%, 68% and 51% of respondents.ConclusionDutch GE demonstrate substantial variability in the management of asymptomatic PCNs. A significant proportion of general GE still use ultrasound for surveillance of small PCNs, while GE with EUS experience were more likely to perform EUS. The presence of risk factors for malignant degeneration of IPMN were not recognized by a substantial proportion of GE. Data on the natural history of PCNs is required to provide input for evidence-based guidelines, which should lead to a more uniform approach.  相似文献   
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