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31.
We report an unusual type of mucinous cystadenoma of the pancreas, characterised by a predominantly solid gross appearance due to the presence of an abundant ovarian-type stroma. The tumour, located in the body of the pancreas, was discovered after episodes of acute pancreatitis. It was composed of several mucus-secreting benign cysts placed within a highly cellular ovarian-type stroma, composed of undifferentiated spindle cells with mild atypia but without any increase of mitotic activity and with a low proliferative index. These cells expressed oestrogen and progesterone receptors, but they did not express CD34, CD117, p53 protein or bcl-2. Recognition of this peculiar mainly solid mucinous cystadenoma containing an abundant ovarian-type stroma is difficult. It is conceivable that the mesenchymal component described in our case could represent an early stage in the development of sarcoma in mucinous cystadenoma of the pancreas.  相似文献   
32.
The specific cellular immune response to the partially purified pancreatic antigen was studied by the peripheral blood lymphocyte proliferation assay in patients with chronic pancreatitis, Sjögren's syndrome, and primary biliary cirrhosis. A significant positive result (stimulation index >2.0) was observed in 7 of 21 patients with idiopathic chronic pancreatitis (33%;P<0.05), 6 of 7 patients with Sjögren's syndrome-associated chronic pancreatitis (86%;P<0.0005), and 6 of 11 patients with Sjögren's syndrome (55%;P<0.01), compared to normal controls whose stimulation index was 0.94±0.28 (mean ± SD;n=14; range, 0.56–1.60). On the other hand, patients with alcoholic chronic pancreatitis (17%;n=12), stone-related chronic pancreatitis (0%;n=7), primary biliary cirrhosis-associated chronic pancreatitis (33%;n=3), primary biliary cirrhosis (0%;n=4), systemic lupus erythematosus (17%;n=6), and autoimmune thyroiditis (0%;n=6) showed no significant difference from normal controls. Furthermore, in patients with idiopathic chronic pancreatitis who had positive results, a lymphocyte proliferative response to the pancreatic antigen was observed in T cells, especially in the CD4+ T cell subpopulation. These results suggest that the pancreatic antigen plays a role in the pathogenesis of a part of idiopathic chronic pancreatitis and Sjögren's syndrome in association with T cell responses and, also, suggest that autoimmunity may be a possible etiological factor in chronic pancreatitis.  相似文献   
33.
A 53-yr-old woman presented with a left upper quadrant abdominal mass attached to the body of the pancreas. Fine-needle aspiration (FNA) yielded cyst fluid containing numerous benign, mature squamous cells, keratin debris, and inflammatory cells. The diagnosis of dermoid cyst was subsequently rendered on the resected specimen. The cytologic and histologic features are presented. FNA cytology proves to be a valuable diagnostic adjunct in the preoperative evaluation of a patient with dermoid cyst of the pancreas.  相似文献   
34.
Epithelial cadherin (E-cadherin) is a Ca2+-dependent cell-cell adhesion molecule that connects cells via homotypic interactions. Its function is critical in the induction and maintenance of cell polarity and differentiation, and its loss of downregulation is associated with an invasive and poorly differentiated phenotype in colon and other tumours. We have used an avidin-biotin immunoperoxidase technique to localize E-cadherin in microwave-treated, paraffin-embedded sections from 36 patients with pancreatic adenocarcinomas. E-cadherin was expressed by normal ductal and acinar cells with typical membranous staining at the intercellular junctions. Loss of normal surface E-cadherin expression was found in 19/36 (53 per cent) tumours compared to the adjacent normal ductal cells. Abnormal E-cadherin expression was found more frequently in poorly differentiated (grade III) (6/7, 86 per cent) than in well-differentiated tumours (grade I) (4/14, 28 per cent) (P=0·012). Membranous E-cadherin expression was also lost more frequently in primary tumours with lymph node (stage III) (14/23, 61 per cent) and distant metastasis (stage IV) (2/2, 100 per cent) compared with 3/11 (27 per cent) lymph node-negative tumours (stage I) (P=0·043). In conclusions, our data indicate that loss of membranous E-cadherin expression is associated with high grade and advanced stage in pancreatic cancer.  相似文献   
35.
We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine carcinomas. Received: 14 April 1999 / Accepted: 7 July 1999  相似文献   
36.
A case of basaloid carcinoma of the pancreas in a 26-year-old woman is reported. The tumour was constituted by solid nests of relatively uniform neoplastic cells with hyperchromatic nuclei and scant cytoplasm, showing distinct peripheral palisading. There were necrotic areas and deposition of hyaline material, suggesting a basement membrane-like substance. Small foci of clear-cut squamous differentiation were present. Tumour cells were positive for cytokeratin 14 and P63 and negative for neuroendocrine and acinic cell markers. Ultrastructurally, the tumour was constituted by polygonal cells with round nuclei containing clumped chromatin. Occasional tight junctions and keratin filaments were present. Basaloid carcinomas may arise in several sites of the body, the most frequent being the anus and oesophagus, and have poor clinical outcome. The present case appears to be, to the best of our knowledge, the first documented example in the literature of basaloid carcinoma of the pancreas.  相似文献   
37.
The incidence of pancreatic adenocarcinoma is increasing and it is usually unresectable at the time of diagnosis. Consequently, fine-needle aspiration biopsy (FNAB) is being used more frequently for diagnosis. The reported sensitivity of diagnosing pancreatic adenocarcinoma by FNAB has varied between 50% and 100%. In an attempt to increase the diagnostic sensitivity, we retrospectively reviewed a series of pancreatic FNABs. Fifteen cytologic criteria were evaluated in 78 patients who had pancreatic FNABs. Of these patients, 49 had primary adenocarcinomas and 29 had benign, non-neoplastic lesions. Using a stepwise logistic regression analysis we identified three key cytologic criteria for this diagnosis. Our study identified anisonucleosis (P = 0.001), large nuclei (P = .007), and nuclear molding (P = .03) as the significant cytologic features for diagnosing pancreatic adenocarcinoma. In combination, these three criteria had a sensitivity of 98% and a specificity of 100%.  相似文献   
38.
A systematic study of the vascularisation of the pancreas   总被引:3,自引:0,他引:3  
Summary The anatomy of the vessels of the pancreas is well known. However, some refinement is necessary in response to new requirements. In this study 40 specimens of pancreas plus duodenum were dissected after injecting the vessels with latex. Arteries and veins were measured and drawn. The origin and course of the vessels and their anastomoses were studied. If the vessels less than 0,5 mm in diameter are disregarded, it is seen that the vascularisation of the head of the pancreas can be systematised. Since the development of very selective arteriography and phlebography, two main types of artery and of vein have been discerned. Charts of the vessels for such an identification have been suggested. The two types of vessel are either terminal or anastomotic. Determination of the type of vessel can be useful: for the localisation of endocrine tumors of the pancreas by selective catheterisation; in making the decision for a limited operative intervention when immediate effective blood supply of the remaining tissue is important.This work was carried out in the Anatomy Laboratory of Université René-Descartes (Paris V) in collaboration with the Service d'Anatomo-Pathologie of the Hôpital du Kremlin-Bicêtre  相似文献   
39.
Fine-needle aspiration biopsy of the pancreas: a study of 61 cases   总被引:1,自引:0,他引:1  
Eighty-six fine-needle aspirates (FNAs) of pancreas from 74 patients were reviewed. Histological confirmation or clinical follow-up of the final diagnosis was available in 61 aspirates from 49 patients. Of 42 proven malignant cases, FNAs were diagnosed as positive in 21 (50%), suspicious in 4 (9.5%), negative in 12 (28.6%), and unsatisfactory in 5 (11.9%). Of 19 proven benign cases, FNAs were diagnosed as negative in 15 (78.9%) and unsatisfactory in 4 (21%). This resulted in a 50% sensitivity, a 100% specificity, a diagnostic efficiency of 59%, a predictive value of a positive test of 100%, and a predictive value of a negative test of 55.6%. Thirty-six primary pancreatic adenocarcinomas and six metastatic tumors to the pancreas were encountered. Benign cases were attributed to anatomical pancreatic variants, acute pancreatitis, abscess, chronic pancreatitis, and pseudocysts. Pancreatic FNA was safe, accurate, and relatively inexpensive, but it was relatively insensitive in the diagnosis of malignancy.  相似文献   
40.
Summary The isolated rabbit pancreas secretes protein and -amylase at a relatively constant rate during an eight-hour period. Ouabain (10–5 and 10–6 M) did not alter enzyme secretion, but inhibited flow (65% and 28% respectively). Acetazolamide (10–3 M) had no effect on pancreatic enzyme secretion, while flow was inhibited by 25%. Na azide (10–2 M) failed to affect protein and -amylase secretion. Flow was inhibited by approximately 88%. NaF (10–2M) increased both protein and -amylase secretion, while flow remained virtually unchanged. Gassing of the bathing fluid with 95% N2–5% CO2 reduced protein and -amylase secretion by 57 and 64% respectively, while flow was decreased by 77%. Lowering of the sodium concentration in the bathing fluid by 85% decreased -amylase secretion by 46%. Flow was inhibited by 77%. Return to the standard solution caused initially an increase of -amylase secretion (86%), followed by a decrease. These results strongly suggest that the enzyme secretion of the pancreas is not coupled to the sodium pump, responsible for fluid and electrolyte secretion.  相似文献   
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