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G Molas

Publications and source records attributed to G Molas.

118 records · Page 7Linked to original sources

[Immunohistochemical and ultrastructural heterogeneity of gastrointestinal stromal tumors].

AIMS AND METHODS: Digestive stromal tumors are the most frequent undifferentiated mesenchymal tumors. The prognosis of these tumors is difficult to predict and the histogenesis is still subject to controversy. However, the frequent and specific expression of CD117 (c-kit) by these tumors could suggest an origin from interstitial cells of Cajal. The aim of this study was to analyse the histological and immunohistochemical characteristics of 46 digestive stromal tumors surgically resected, with comparaison of CD34 and CD117 expression in these tumors. Sixteen tumors were analyzed on electron microscopy. RESULTS: Sixty three and 74% of the stromal tumors were positive for CD117 and CD34 respectively. While CD117 expression was similar in all locations, on the contrary, there was a decreasing gradient of CD34 expression between gastric (87%) and jejunal (33%) tumors. All tumors with skeinoid fibers expressed CD117. Focal expression of smooth muscle actin was noted in 43% of the cases. The ultrastructural study showed no correlation with the immunohistochemical results. CONCLUSION: Digestive stromal tumors show an immunophenotypic and ultrastructural heterogeneity. CD117 expression is frequent, but not constant.

Adult↗

[Hepatocellular carcinoma in undamaged liver].

Hepatocellular carcinoma mainly affects patients with cirrhosis or with various degrees of fibrosis. From 1979 to 1990, among 87 patients who underwent hepatic resection for non fibrolamellar hepatocellular carcinoma, 12 (14%) had a non fibrolamellar hepatocellular carcinoma developed in a normal liver. There were 8 men and 4 women, aged 29 to 74 years. In 7 patients (58%) hepatocellular carcinoma was associated with clinical manifestations. Serum hepatitis B surface antigen were absent in all patients. Serum alphafetoprotein level was less than 100 mg/ml in 10 (83%), size of the tumor was greater than or less than 5 cm in 10 (83%) and capsule was present in 10 (83%). Resections included removal of 2 segments or more in 11 (91%). One patient died postoperatively. Actuarial survival rate at 3 and 5 years were respectively 57% and 38%. Intra or extrahepatic recurrence was recognized in 8 (67%), 2 patients were alive respectively 28 and 16 months after treatment of their intrahepatic recurrence (resection in one and intra-arterial embolisation in one). In conclusion, our results suggest that aggressive surgical efforts are justified in non fibrolamellar hepatocellular carcinoma arising in normal liver.

Adult↗

[Pancreatic intraductal adenoma, adenomatosis and adenocarcinoma].

Three cases of adenomatous lesions of the pancreatic ducts are reported. There was 1 case each of adenoma of the main pancreatic duct, adenomas of the uncinate process and diffuse adenomatosis of the cephalic pancreatic ducts with ampullary involvement. On ultrasound and computerized tomography, the main pancreatic duct was enlarged in all cases, associated in 2 cases with a mass in the head of the pancreas, and in 1 case, with pseudocystic dilation of the uncinate process ducts. At duodenoscopy, the papilla was tumoral in 1 case, enlarged with mucous flow in 1 case and normal in the third case in which cytologic examination of secretions disclosed glandular cells. Endoluminal lesions were diagnosed by endoscopic retrograde pancreatography in 2 cases and on gross pathologic examination in 1 case. Treatment was surgical: cephalic pancreatoduodenectomy in 2 cases and local resection in 1 case, which relapsed 3 years later. At pathology, lesions were benign in all 3 cases including 1 case of severe dysplasia. On the basis of these 3 cases and a review of the literature, distinctive features of pancreatic endoluminal adenomas and adenocarcinomas are specified. Pancreatic resection is mandatory because of the risk of pancreatic obstruction and malignant degeneration.

Adenocarcinoma↗

[Focal lymphoid hyperplasia (pseudolymphoma) of the terminal ileum in adults].

We report two cases of focal lymphoid hyperplasia (FLH) of terminal ileum in adult patients. Both cases showed identical morphological findings. The first was discovered during cholecystectomy in a 75-year-old woman who complained mild non-specific abdominal discomfort. The second was manifested by right lower quadrant abdominal pain in a 32-year-old man. The surgical specimens revealed a thickened wall, a narrowed lumen and multiple ulcerations. The histologic features were small cell, well differentiated lymphocyte infiltration, with several follicles showing large germinal centers; regional lymph nodes revealed a conspicuous reactive size enlargement. Further clinical investigations revealed no other abnormalities. Clinical course showed benign evolution after 6 and 3 years of respective follow-up. FLH should be differentiated from terminal ileum inflammatory and infectious diseases. It can be differentiated from Crohn's disease by the absence of characteristic histological features; from Yersinia infection by the absence of significant rates of specific serum antibodies. Moreover, FLH can be differentiated from malignant lymphoma by the presence of follicles and enlarged germinal centers and by the long-term benign evolution. The nature of FLH in terminal ileum, as well as those of the stomach and colo-rectum is still to be determined. Several hypothesis are proposed: reactive, benign neoplastic, or prelymphomatous lesion?

Adult↗

[Free fatty acids and acute pancreatitis. An in vivo experimental study].

Experimental in vitro studies support a theory which attributes a key role to pancreatic lipase in the physiopathology of acute pancreatitis. Pancreatic lipase would hydrolyse triglycerides either in circulation or in tissues, releasing Free Fatty Acids (F.F.A.). These F.F.A. would contribute to the genesis of necrotizing lesions by their detergent properties. This experimental work, tried to confirm this theory in vivo in rats, using the cerulein-induced pancreatitis model (four injections 20 micrograms/kg of cerulein subcutaneously). It has been demonstrated first that a five-times increase of circulating plasma F.F.A. (3.02 +/- 0.28 mmol/l versus 0.75 +/- 0.05 mmol/l in control) dit not worsen cerulein-induced pancreatitis and were rather protective than deleterious. Furthermore, F.F.A. levels did not increase either in portal and aortic plasma during these pancreatitis, despite a major lipase release. There was also no increase of pancreatic content of F.F.A., measured by organic extraction performed on pancreatic homogenates. The role commonly attributed to F.F.A. in acute pancreatitis, based on in vitro experiments seems questionable in vivo.

Acute Disease↗