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101.
异位胰腺伴导管内乳头状黏液性肿瘤形成是一种罕见的疾病,国内鲜见报道,主要位于胃、肝内胆管和小肠。本文报道1例病例,病变位于胃壁,术前超声内镜显示病变位于黏膜下层,内部回声局部呈中高回声,可见囊腔样无回声区,经内镜黏膜下剥离术完整切除,术后病理为异位胰腺伴导管内乳头状黏液性肿瘤(胃型)。  相似文献   
102.
Pancreatic cancer currently has no subtypes that inform clinical decisions; hence, there exists an opportunity to rearrange the morphological and molecular taxonomy that guides a better understanding of tumor characteristics. Nonetheless, accumulating studies to date have revealed the large-duct type variant, a unique subtype of pancreatic ductal adenocarcinoma (PDA) with cystic features. This subtype often radiographically mimics intraductal papillary mucinous neoplasms (IPMNs) and involves multiple small cysts occasionally associated with solid masses. The “bunch-of-grapes” sign, an imaging characteristic of IPMNs, is absent in large-duct PDA. Large-duct PDA defines the mucin profile, and genetic alterations are useful in distinguishing large-duct PDA from IPMNs. Histologically, neoplastic ducts measure over 0.5 mm, forming large ductal elements. Similar to classic PDAs, this subtype is frequently accompanied by perineural invasion and abundant desmoplastic reactions, and KRAS mutations in codon 12 are nearly ubiquitous. Despite such morphological similarities with IPMNs, the prognosis of large-duct PDA is equivalent to that of classic PDA. Differential diagnosis is therefore essential.  相似文献   
103.
《Pancreatology》2022,22(3):435-442
BackgroundThe diagnosis of type 2 autoimmune pancreatitis (AIP) is dependent on typical radiologic imaging and the presence of the granulocytic epithelial lesion (GEL), which is characterized by ductal neutrophilic infiltration with or without neutrophilic acinar infiltration.MethodsWe evaluated GEL and related clinicopathologic factors in 165 resected heterotopic pancreata (HPs) [57 gastric (35%), 56 duodenal (34%), 30 omental (18%), and 22 jejunal (13%)] and 29 matched orthotopic pancreata routinely examined during surgery.ResultsGEL was noted in 8% (13/165) of HPs, including ductal epithelial (6/13, 46%) and intraluminal (8/13, 62%) neutrophilic infiltrations. However, there was no GEL in orthotopic pancreata. Abdominal pain was observed in 6 (46%) patients with GEL-positive HPs. GEL was more commonly observed in HPs having symptoms (p = 0.029), a larger size (p = 0.028), and an infiltrative growth pattern (p = 0.006). In addition, periductal lymphoplasmacytic infiltration and fibrosis (both p < 0.001), interstitial fibrosis (p = 0.017), acinar neutrophilic infiltration (p = 0.032), venulitis (p = 0.050), acinar ductal metaplasia (ADM; p = 0.040), and pancreatic intraepithelial neoplasia/intraductal papillary mucinous neoplasms (PanIN/IPMN; p < 0.001) were more commonly seen in HPs with GEL than in those without GEL. Inflammatory bowel disease was present only in one patient with GEL-negative HP.ConclusionsGELs are detected in a subset of HPs without clinical evidence of AIP. Therefore, for the diagnosis of AIP, GEL should be carefully interpreted with the context of other histologic, clinical, and radiologic findings.  相似文献   
104.
An arteriovenous malformation of the pancreas is a very rare disease, but its presentation is distinct and unique. In this report, we describe a patient who presented with this malformation which was localized in the tail of pancreas and demonstrated by abnormal angiography findings. The patient was a 60-year-old male with severe left hypochondralgia. Angiography revealed an increased blood volume in the tail of the pancreas with arteriovenous shunting. Secondary pancreatitis caused by the arteriovenous malformation was suspected by abnormal laboratory data, and confirmed by histology from the resected tail of the pancreas. This is a very rare report in which pancreatic arteriovenous malformation involving a pancreaticovenous fistula was confirmed by endoscopic retrograde cholangiopancreatography (ERCP).  相似文献   
105.
Summary A carcinoma in the dorsal part of the pancreas divisum with an annular pancreas in the anterior part is reported. A 79-yr-old female was admitted in our hospital complaining of epigastralgia. Computed tomography (CT) and ultrasound (US) showed an irregular mass in the pancreatic body. A pancreatogram obtained through the major duodenal papilla demonstrated only the ventral pancreatic duct that encircled the duodenum. Contrast medium injected from the minor duodenal papilla showed Santorini’s duct obstruction at the neck portion of the pancreas without communication with the ventral pancreatic duct. The patient died with liver metastases. Autopsy confirmed annular pancreas and a 6-cm tumor in the pancreatic body extending to the pancreatic head and pancreas divisum. Pancreatic carcinoma; histologically a moderately differentiated adenocarcinoma; originated from the dorsal part of pancreas divisum. To our knowledge this is the first report of pancreatic carcinoma associated with annular pancreas coexistent with pancreas divisum.  相似文献   
106.
We describe a rare case of pancreas divisum associated with a giant retention cyst (cystic dilatation of the dorsal pancreatic duct), presumably formed following obstruction of the minor papilla. The patient was treated by pancreatico(cysto)jejunostomy. A 50-year-old man was admitted with complaints of increasing upper abdominal distension and body weight loss. There was no previous history of pancreatitis, gallstones, drinking, or abdominal injury. An elastic-hard tumor-like resistance was palpable in the upper abdomen. Computed tomography and ultrasound (US) examinations revealed a giant cystic lesion expanding from the pancreas head to the tail. Endoscopic retrograde cholangiopancreatography findings showed a looping pancreatic duct which drained only the head and uncinate process of the pancreas to the main papilla. A US-guided puncture to the cystic lesion revealed that the lesion continued to the main pancreatic duct in the tail of pancreas. The lesion was connected to a small cystic lesion, which was located inside the minor papilla, and ended there. The amylase level in liquid aspirated from the cyst was 37 869 IU/l, and the result of cytological examination of the liquid showed class II. A pancreatico(cysto)jejunostomy was performed, with the diagnosis being pancreas divisum associated with a retention cyst following obstruction of the minor papilla. The histological findings of a specimen from the cyst wall revealed that the wall was a pancreatic duct covered with mildly inflammatory duct epithelium; there was no evidence of neoplasm. The patient is currently well, and a CT examination 2 years after the operation showed disappearance of the cyst and normal appearance of the whole pancreas. Received: April 24, 2001 / Accepted: September 14, 2001  相似文献   
107.
Leptin inhibition of insulin secretion from isolated human islets   总被引:10,自引:0,他引:10  
Leptin is a hormone produced and secreted from the adipose tissue. Its physiological actions include the regulation of satiety, food intake and energy balance. The production of leptin is increased by high insulin levels. Here, we demonstrate that leptin acts as an inhibitor of glucose-induced (20 mM) insulin secretion from isolated human islets. No effect was observed in the presence of lower glucose levels (2.8 and 10 mM glucose). The pancreatic β-cell might represent a target of a direct physiological action of leptin. We suggest the presence of an “adipo-insular axis” in which leptin mediates negative feedback from the adipose tissue to the endocrine pancreas. Received: 21 July 1997 / Accepted in revised form: 1 October 1997  相似文献   
108.
Most cystic lesions of the pancreas are nonneoplastic and inflammatory in nature. However, approximately 5%–15% of cystic pancreatic masses may be neoplastic. Among the cystic neoplasms are the mucin-producing tumors, both the intraductal papillary mucinous neoplasms and the mucinous cystic neoplasms. Their imaging features on contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) can assist in the differentiation of these lesions. The imaging findings of both intraductal papillary mucinous neoplasm and mucinous cystic neoplasm are reviewed with attention to CT and MRI.  相似文献   
109.
Aims/hypothesis A progressive loss of beta cell function and mass are important contributory factors in the development and progression of type 2 diabetes. The aim of this study was to evaluate the effects of a primary reduction in beta cell mass on beta cell function in vivo and in the perfused pancreas and to relate these characteristics to beta cell mass.Methods The beta cell mass of six Göttingen minipigs was reduced chemically (using 67 mg/kg nicotinamide and 125 mg/kg streptozotocin). Six untreated minipigs were kept as control animals. Insulin responses were evaluated in vivo using the mixed meal tolerance test (2 g/kg oral glucose) and in the isolated perfused pancreata from the same animals by stimulation with glucose, glucagon-like peptide-1 or arginine.Results Beta cell mass was reduced in the beta-cell-reduced animals compared with the control minipigs (182±76 vs 464±156 mg, p<0.01). AUCglucose was increased in the beta-cell-reduced animals (1383±385 vs 853±113 mmol·l–1·min in control minipigs, p<0.01), as was the insulin response to oral glucose per unit of beta cell mass (123±84 vs 56±24 pmol·l–1·min·mg–1, p<0.05). Total in vitro insulin secretion was increased per unit of beta cell mass in nicotinamide + streptozotocin pancreata compared to controls (83.7±45.9 vs 34.6±14.4 nmol/mg beta cells, p<0.05) with responses to glucose and glucagon-like peptide-1 showing a partial compensation for reduced beta cell mass, whereas no compensation was seen in response to arginine.Conclusions/interpretation A primary reduction in beta cell mass impairs glucose tolerance and leads to a compensatory increase in insulin secretion from the remaining beta cells after oral glucose in vivo, which is even more apparent in the perfused pancreas. It remains to be determined whether this compensation can be maintained in the long term.Conflict of interest statement: M.O. Larsen, B. Rolin, C.F. Gotfredsen and R.D. Carr are all employees and shareholders at Novo Nordisk. J.J. Holst has been on advisory boards for Novo Nordisk.  相似文献   
110.
A case of solitary neurofibroma in the retroperitoneum involving the uncinate process of the pancreas, which has been reported in only one case in Japan and less than 20 cases in the world literature, is described. A 57-year-old male complained of back pain and microhematuria. Plain and enhanced abdominal computed tomography (CT) indicated an 8 × 6 cm hypovasular tumor located in the uncinate process. We initially assumed it to be a cancer of the pancreas. His physical examination and blood chemistry result were normal. Various diagnostic imaging methods however, disclosed a rare type of tumor. The tumor was resected by pancreaticoduodenectomy and histological examination revealed it to be neurofibroma.  相似文献   
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