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Anne Couvelard

Publications and source records attributed to Anne Couvelard.

At least 37 records · Page 2Linked to original sources
PubMed2004

Mucinous cystadenoma with mesenchymal over-growth: a new variant among pancreatic mucinous cystadenomas?

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.

Adult↗
PubMed2004

Clinical and autopsy diagnoses in the intensive care unit: a prospective study.

BACKGROUND: Autopsy rates have declined worldwide, but recent retrospective intensive care unit (ICU) data indicate major discrepancies between more than 25% of clinical and autopsy diagnoses. METHODS: We conducted a 3-year prospective study of all consecutive autopsies performed on patients who died in a university hospital medical-surgical ICU to determine how many might have benefited from a different level of care, had the autopsy diagnosis been made before death. All clinical diagnoses were compared with autopsy findings at monthly clinical-pathological meetings. Major and minor diagnostic discrepancies were categorized according to the criteria of Goldman et al. RESULTS: Of 1492 patients admitted to the ICU, 315 died, of whom 167 (53.0%) were autopsied. The most common reason (79.7%) for not obtaining an autopsy was family refusal. The mean +/- SD clinical characteristics were similar for autopsied vs nonautopsied patients, except for shorter length of ICU stay (13 +/- 17 vs 20 +/- 27 days, P =.006), shorter duration of mechanical ventilation (13 +/- 16 vs 19 +/- 25 days, P =.01), and lower percentage of postcardiac surgery patients (38.9% vs 50.0%, P =.05). Among the intensivists' 694 clinical diagnoses, 33 (4.8%) were refuted and 13 (1.9%) were judged incomplete by autopsy findings. Autopsies revealed 171 missed diagnoses, including 21 cancers, 12 strokes, 11 myocardial infarctions, 10 pulmonary emboli, and 9 endocarditis, among others. Major diagnostic errors (class I and class II discrepancies) were made in 53 (31.7%) of 167 patients, with a high percentage of immunocompromised patients also observed among these. Similar percentages of patients with class I and class II errors vs other patients had undergone modern diagnostic techniques during their ICU stay. CONCLUSION: Even in the era of modern diagnostic technology, regular comparisons of clinical and autopsy diagnoses provide pertinent information that might improve future management of ICU patients.

Aged↗
PubMed2004

Correlation between patterns of DNA mismatch repair hmlh1 and hmsh2 protein expression and progression of dysplasia in intraductal papillary mucinous neoplasms of the pancreas.

Defective DNA mismatch repair results from genetic or epigenetic alterations that most frequently inactivate the genes hMLH1 and hMSH2. This is thought to promote tumourigenesis by accumulation of mutations in oncogenes and tumour suppressor genes. This pathway, first reported in colon cancer, has been recently demonstrated in a subgroup of sporadic pancreatic adenocarcinomas. Intraductal papillary-mucinous neoplasms of the pancreas are a special type of pancreatic tumours, characterised by a spectrum of morphological changes from mild to moderate and to non-invasive, and they may associate with adenocarcinoma. An immunohistochemical study of hmlh1 and hmsh2 protein expression was performed on 26 intraductal papillary-mucinous neoplasms. All tumours showed nuclear expression of hmlh1 and hmsh2 proteins. There were two distinctive patterns of protein expression on the basis of the location of cells expressing these markers: the "normal" pattern, observed mainly in adenoma and rarely in intraductal papillary-mucinous neoplasms with moderate dysplasia and the "dysplastic" pattern, frequently encountered in moderate dysplasia neoplasms, non-invasive and invasive carcinomas. These findings suggest that defective DNA mismatch repair, due to inactivation of hMLH1 and hMSH2, does not play a significant role in the pathogenesis of intraductal papillary-mucinous neoplasms of the pancreas. Two patterns of protein expression were observed and were correlated with the progression of dysplasia in intraductal papillary mucinous neoplasms.

Adaptor Proteins, Signal Transducing↗
PubMed2004

Early expression of adhesion molecules after lung transplantation: evidence for a role of aggregated P-selectin-positive platelets in human primary graft failure.

BACKGROUND: Primary graft failure (PGF) secondary to ischemia-reperfusion injury is the main cause of death in the first month after lung transplantation. The aim of this study was to identify early cellular and immunologic events associated with PGF in human lung transplants. METHODS: Induction of P-selectin, E-selectin and intercellular adhesion molecule-1 (ICAM-1) and evaluation of leukocytes and platelets accumulation were investigated in 18 post-reperfusion surgical specimens of lung allografts by an immunohistochemical technique. RESULTS: Selectins were restricted to the venular plexus after reperfusion as in the normal lung, whereas ICAM-1 was induced in all cases on alveolar capillaries. Numerous polymorphonuclear cells (18 of 18 cases) and aggregated platelets (7 of 18 cases) were identified along the venular plexus after reperfusion. Compared with the other patients, those with aggregated P-selectin-positive platelets were characterized by a longer duration of mechanical ventilation (p < 0.01), a lower PaO2/FiO2 ratio (p < 0.01) and the presence of radiologic edema (p < 0.05) within the first 3 post-operative days. CONCLUSIONS: We showed in the reperfused lung a distinct expression of adhesion molecules on venous and capillary pulmonary endothelia that may influence the role of leukocytes and platelets during the early course of transplantation. Furthermore, the knowledge of an association between the presence of P-selectin-positive platelet aggregates and PGF criteria might have implications for graft management and therapeutic strategies.

Blood Platelets↗
PubMed2004

Macrocystic pancreatic cystadenoma: The role of EUS and cyst fluid analysis in distinguishing mucinous and serous lesions.

BACKGROUND: Benign pancreatic serous cystadenoma usually is morphologically distinguishable from mucinous cystadenomas, which require resection because of their malignant potential. A macrocystic variant of serous cystadenoma recently has been described, rendering this important distinction more difficult. The aim of this study was to determine the EUS and tumor marker characteristics of mucinous cystadenoma compared with macrocystic serous cystadenomas. METHODS: Medical records for consecutive patients seen between 1995 and 2002, with a histopathologic diagnosis of mucinous cystadenoma or macrocystic serous cystadenoma after surgery, who had undergone a detailed EUS examination, including EUS-guided FNA, were retrospectively reviewed. RESULTS: A resection specimen was available for 32 mucinous cystadenomas and 9 macrocystic serous cystadenomas. No significant differences were observed with regard to clinical data (age, gender, presence of symptoms), lesion size, and location within the pancreas. All mucinous cystadenomas had a discernible cyst wall (thickened, 66%; focal parietal nodules, 25%) compared with 56% of macrocystic serous cystadenomas (p<0.0001). A thick echo content also was more frequent in mucinous cystadenoma (56% vs. 11%; p=0.04; statistical significance removed by the Bonferroni correction). Microcysts were only observed in macrocystic serous cystadenomas (44%; p=0.0008). The combination of a cyst wall that is thickened and the absence of microcysts had a sensitivity of 100% and specificity of 78% for the diagnosis of mucinous cystadenoma compared with macrocystic serous cystadenoma. Although intracystic carbohydrate-associated antigen 72-4 and mucins M1 were non-discriminatory, low carcinoembryonic antigen (<5 ng/mL) and carbohydrate-associated antigen 19-9 (<50,000 U/mL) values were found in macrocystic serous lesions (respectively, 100% and 100%; p=0.0002 and p=0.0002). CONCLUSIONS: Although there is considerable overlap, helpful EUS characteristics that differentiate mucinous cystadenoma from macrocystic serous cystadenoma include a thick cyst wall and microcysts. These features, coupled with analysis of aspirated fluid for tumor markers (especially carcinoembryonic antigen), should help to confirm the diagnosis.

Adolescent↗
PubMed2003

Intraductal papillary mucinous tumors of the pancreas: the preoperative value of cytologic and histopathologic diagnosis.

BACKGROUND: The preoperative diagnosis of intraductal papillary mucinous tumors of the pancreas must be as certain as possible because removal of a large portion of the pancreas or even total pancreatectomy may be necessary. The value of cytologic and histopathologic analysis of specimens obtained by preoperative endoscopic investigations is unknown. The aim of this study was to assess the value of such analyses of specimens obtained by EUS-guided FNA and/or biopsy, or transpapillary biopsy specimens obtained during endoscopic retrograde pancreatography for the diagnosis of intraductal papillary mucinous tumors of the pancreas and for the detection of malignancy. METHODS: Between 1992 and 2001, 42 patients (22 men, 20 women; median age 64 years) underwent surgical resection for intraductal papillary mucinous tumors of the pancreas and had preoperative pancreatic tissue sampling. In the case of isolated dilatation of pancreatic ducts, pancreatic juice was obtained by EUS-guided FNA for cytologic analysis. In the presence of a solid lesion or main pancreatic duct stenosis, biopsy specimens were obtained by EUS-guided FNA biopsy or endoscopic retrograde pancreatography, which permitted histopathologic assessment. The accuracy of cytology and histopathology was evaluated for the following: (1) positive diagnosis of intraductal papillary mucinous tumors of the pancreas and (2) assessment of malignancy, by comparison with histopathologic examination of surgical resection specimens. RESULTS: Cytologic analysis was performed in 19 patients; it was positive in 4 (21%) and noninformative in 15 (79%). Histopathologic analysis was performed in 23 patients; it was positive in 21 (91%) and negative in 2 (9%). Histopathologic analysis yielded a positive result in 83% of patients who did not have extrusion of mucus from a patulous papilla. The sensitivity, specificity, and positive and negative predictive values of histopathologic analysis for the diagnosis of malignancy were, respectively, 44%, 100%, 100%, and 33%. When histopathologic analysis was positive, the tumor grade was similar to that determined by final histopathologic examination in 38% of patients, whereas the grade was underestimated in 62%. No complication occurred as a result of tissue sampling. CONCLUSIONS: The sensitivity of histopathologic analysis of EUS-guided FNA biopsy specimens or transpapillary biopsy specimens is 91% for the positive diagnosis of intraductal papillary mucinous tumors of the pancreas with a solid component, which is of particular interest as extrusion mucus from the papilla was absent in most patients. Histopathologic analysis of biopsy specimens of malignant intraductal papillary mucinous tumors of the pancreas often underestimates tumor grade. The result for cytologic analysis of juice obtained from dilated pancreatic ducts is disappointing.

Aged↗
PubMed2003

Adenomyoma and adenomyomatous hyperplasia of the Vaterian system: clinical, pathological, and new immunohistochemical features of 13 cases.

Adenomyoma and adenomyomatous hyperplasia of the Vaterian system are consistently benign lesions. Clinically, adenomyoma mimics frequently ampullary adenoma or carcinoma, and biopsy analysis is often difficult. The histogenesis of ampullary adenomyoma and adenomyomatous hyperplasia is still subject to debate. We present a retrospective study of clinicopathological features of 13 cases of surgically resected ampullary adenomyoma. The age of our patients was between 38 and 78 years (mean: 63 y). The preoperative diagnosis was ampullary tumor or tumor of the head of the pancreas. On macroscopy, a white, firm lesion of the ampullary wall was observed; its size ranged between 10 and 30 mm. Histologically the lesion consisted of multiple glandular structures surrounded by a fibroblastic/myofibroblastic proliferation, resulting in a "pseudo-hypertrophy" of the Vaterian system. The immunophenotype of the epithelial component was cytokeratin 7+/cytokeratin 20-, similar to that of the normal biliary and pancreatic duct system. The epithelial cells exhibited low proliferative activity. The hyperplastic myofibroblastic cells expressed smooth muscle actin. A complete pancreatic heterotopy contiguous with the adenomyoma was noted in three cases. Adenomyoma and adenomyomatous hyperplasia of the Vaterian system are benign lesions frequently treated by extensive surgery because of long-term biliary obstruction. The clinicopathological characteristics suggest either a reactive and/or a malformative, nonneoplastic nature for this lesion, which could, in some cases, develop from heterotopic pancreas. The immunophenotype of epithelial cells may be a useful tool for differentiating it from ampullary adenoma on biopsy specimens.

Adenomyoma↗
PubMed2002

Mucin gene expression in intraductal papillary-mucinous pancreatic tumours and related lesions.

Intraductal papillary-mucinous tumours (IPMTs) of the pancreas are heterogeneous proliferations characterized by a malignant potential. The molecular mechanisms underlying the tumourigenesis process are not well understood. Recently, it has been shown that IPMTs secreting the mucin antigen MUC2 have a better prognosis, but the complete pattern of MUC gene expression has not yet been established. The aims of this study were to evaluate the mucin gene expression in 57 IPMTs and eight related lesions surgically resected and to relate MUC gene expression to the histological diagnosis. In situ hybridization (ISH) was performed in 28 cases with probes specific for the MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6, and MUC7 genes. An immunohistochemical analysis was carried in all 65 cases and in 90 conventional ductal adenocarcinomas of the pancreas using MUC1, MUC2, and MUC5AC antibodies. IPMTs of adenoma (dysplasia) type exhibited high expression of MUC2 (93%), MUC5AC (97%), and, to a lesser extent, of MUC4 (71%), all of which were also observed in colloid carcinomas associated with IPMTs. In contrast, IPMTs with simple hyperplasia, intraductal oncocytic papillary neoplasms, and pyloric glandular adenomas exhibited little or no expression of MUC2. The mucin expression profile supports the existence of two types of invasive tumour associated with IPMTs: a colloid and an ordinary form. The latter shows a pattern similar to the conventional ductal adenocarcinomas with a loss of MUC2 and a gain of MUC1 and has a greater tendency to metastasize. In conclusion, the altered expression of mucin, characteristic of IPMT of adenoma type and of colloid carcinomas, may contribute to the better clinical outcome of these neoplasms, compared to conventional pancreatic ductal adenocarcinomas.

Adenocarcinoma, Mucinous↗
PubMed2002

Relationship between vascular development and vascular differentiation during liver organogenesis in humans.

BACKGROUNDS/AIMS: The complex vascular architecture characteristic of the normal adult liver is progressively acquired during the fetal life. In this study, we aimed to evaluate the relationship between angiogenesis and vascular differentiation during liver organogenesis. METHODS: We studied, in 51 fetuses of different gestational ages, the expression of markers of endothelial cell differentiation, integrins, pro- and anti-angiogenic extracellular matrix components, vascular endothelial growth factor (VEGF) and its receptors. RESULTS: Three main stages in the development of the vascular architecture of the liver were identified: (a) from 5 to 10 gestation weeks (GW), no evidence of de novo angiogenesis was detected; the vessels present in the liver primordium were the precursors of portal veins and sinusoids, deriving from preexisting vessels; (b) from 10 to 25 GW, angiogenesis and vasculogenesis resulted in the development of, respectively, arteries and intra-portal capillaries, while portal veins and hepatic sinusoids followed a differentiation process; (c) after 25 GW, little changes were detected in the various vascular compartments. The maximal expression of VEGF and its receptors was from 5 to 25 GW. CONCLUSIONS: The development of the hepatic vascular architecture is a multistep process combining angiogenesis, vasculogenesis and vascular differentiation, regulated by specific growth and differentiation factors including VEGF.

Biomarkers↗
PubMed2002

[Lympho-epithelial cyst of the pancreas: a difficult diagnosis. About two cases].

We report two cases of lymphoepithelial cyst of the pancreas discovered incidentally on imaging in two men aged 50 and 61 years. One cyst contained hyperdense spots on CT-scan and in this case the biochemical analysis of the cyst fluid revealed high level of CEA. The unilocular cysts measured 4 and 5 cm on the surgical specimen. On microscopic examination, the cysts were lined by squamous keratinized epithelium positive for CEA, with rare mucin-secreting cells, lining on lymphoid tissue. The lymphoepithelial cyst is a rare dysembryoplastic benign lesion of the pancreas difficult to diagnose before surgery. The presence of keratin plugs on imaging is inconstant and the biochemical analysis of the cyst fluid can mislead to a diagnosis of mucinous cystic tumour. Cytological and histological analysis of fine needle aspiration material is of diagnostic interest and can avoid surgical resection when patients are symptom-free.

Biopsy, Needle↗
PubMed2002

[Acinar cystic transformation of the pancreas (or acinar cell cystadenoma), a rare and recently described entity].

We report a case of cystic acinar transformation (also known as acinar cell cystadenoma) of the pancreas. A 40-year old woman presented 3 episodes of acute pancreatitis that revealed a multicystic lesion of the ventral part of the head of the pancreas. A Whipple resection was performed. Gross examination of the specimen revealed a well-demarcated multiloculated cyst measuring 4 x 2 cm without communication with the excretory ducts. The cystic spaces contained a non-mucinous fluid. Histological analysis showed numerous various sized cysts that seemed to develop from microcystic structures in the surrounding acinar tissue. The cysts were lined by normal appearing acinar cells, with no atypia, sometimes flattened. Acinar cystic transformation is a rare lesion of the pancreas whose histogenesis is unknown. It should be distinguished from other lesions such as IPMT in order to discuss a surveillance strategy instead of surgical procedure.

Acute Disease↗
PubMedDate not supplied

[Jejunal vipoma].

We report here case of a 57-year-old woman presenting with a metastatic vipoma revealed by secretory diarrhea and severe ionic disorders successfully treated by somatostatin administration. The primitive tumour, located in the jejunum, was identified peroperatively. Both the primitive lesion and the liver metastases were resected at the same time. Early tumour relapse occurred and was unsuccessfully treated by systemic chemotherapy (5-fluorouracil, streptozotocin and doxorubin) and chemoembolization. Finally, a liver transplantation was proposed.

Female↗