Hepatoma in siblings with progressive familial cholestatic cirrhosis of childhood

This report describes four siblings affected with familial intrahepatic cholestasis detected in early infancy. In the two male siblings, biliary cirrhosis and fatal hepatocellular carcinoma later developed, whereas the female siblings have had persistent hepatomegaly and recurrent episodes of cholestasis. Sequential biopsies show that this rare disorder of unknown etiology must be added to the many causes of giant cell transformation of the liver in infancy. Its oncogenic risk, particularly in males, has not been generally appreciated.     

Fibrolamellar carcinoma of the liver in a child: ultrastructural and immunohistologic aspects

We describe a fibrolamellar carcinoma of the liver in a 12-year-old girl and review the literature concerning the occurrence of this distinct hepatic neoplasm in children up to the age of 16 years. The results of our electron microscopic and immunohistologic studies suggest that some cells of this tumor exhibit neuroendocrine differentiation. This finding has important theoretical implications relative to the tumor's histogenesis and practical implications with respect to the search for tumor markers of clinical usefulness and possibly for therapy.     

Histiocytoid hemangioma of the heart with peripheral eosinophilia

A histiocytoid hemangioma of the heart is reported, which was found incidentally in a man with unusually high eosinophilia. The eosinophilia subsided dramatically following removal of the tumor. The "histiocytoid" or the "epithelioid" appearance of the tumor cells and the presence of vacuolated cells were the characteristic microscopic features. The endothelial origin of this tumor was verified by positive immunostaining for factor VIII-related antigen and ultrastructural demonstration of intracytoplasmic lumen formation, abundant cytoplasmic filaments, pinocytotic vesicles, and prominent basal lamina. The presence of mitotic activity, cellular pleomorphism, and tumor necrosis raised the possibility of its malignant potential. The occurrence of this tumor in the heart may be mistaken for a myxoma clinically and a metastatic carcinoma pathologically.     

Omental-mesenteric myxoid hamartomas. Infantile lesions simulating malignant tumors

Three infants presented with multiple nodular tumors of the omentum and mesentery characterized histologically by plump mesenchymal cells in a myxoid, well-vascularized stroma. Electron microscopy of one tumor revealed reticulated inclusions in dilated cisterna of endoplasmic reticulum. Diagnoses by the original pathologist, or by consultants from referral centers in the United States included liposarcoma, primitive sarcoma, possible leiomyosarcoma, and fibromatosis, but the subsequent evolution of the patients questions the validity of such diagnoses. Two patients received what was deemed ineffective therapy, yet survived with no evidence of disease for over a decade of close follow-up. Another patient received no therapy other than the initial surgery, and has been well for more than a year. Infantile lesions may show deceptive features of immaturity and high cellularity that are apt to be confused with a true malignancy. Omentalmesenteric "myxoid" lesions are probably hamartomatous in origin.     

Laryngeal histologic findings in infants with palatal defects with or without craniofacial malformations

The objective of this study was to determine whether specimens from infants with palatal defects (PDs) with or without craniofacial malformations (CFMs) exhibit aberrant laryngeal histologic findings compared with specimens from normal infants. Ten laryngeal specimens from infants with PDs with or without CFMs were histologically compared with 7 laryngeal specimens defined as normal from the same collection. Both groups were similar in terms of demographics and airway manipulation. All infants were prelingual. Comparisons were made at 3 levels: supraglottic, glottic, and subglottic. Histologically, no significant differences in primary laryngeal structures were found between the PD with or without CFM group and the group defined as normal. Acquired and intubation-type injuries, such as inflammation, ulceration, capillary congestion, and scar tissue, were more prevalent and severe in the study group. The primary laryngeal histologic findings of specimens from individuals with PDs with or without CFMs do not differ substantially from those from normal individuals; however, individuals with PDs do appear to be somewhat more susceptible to intubation injury and other acquired laryngeal injury. Meticulous airway management is essential.     

Platelet-activating factor increases mucosal permeability in rat intestine via tyrosine phosphorylation of E-cadherin

1. Platelet-activating factor (PAF), an inflammatory mediator, plays an important role in mediating intestinal injury. However, it remains unclear whether PAF has a function in the intestine. The production of PAF by normal intestine and by unstimulated intestinal epithelial cell lines suggests that PAF may have a regulatory function in the normal bowel. 2. In this study we investigated the role of PAF in modulating intestinal mucosal permeability in rats. Lumen-to-blood transit of FD-4 (dextran 4400), (an index of intestinal permeability), was assessed in sham-operated rats and rats injected with PAF (1.25 microg kg(-1), i.v., a dose insufficient to induce intestinal injury). 3. PAF-induced villus cytoskeletal changes were examined by staining the intestine for F-actin. The effect of PAF on tyrosine phosphorylation of the junctional protein E-cadherin was examined by immunoprecipitation. Some rats were pretreated with AG1288 (a tyrosine kinase inhibitor) before PAF injection, and mucosal permeability change was assessed. 4. To investigate the role of endogenous PAF upon mucosal permeability, we studied the effect of PAF antagonists on (intraluminal) glucose-induced increase in mucosal permeability. 5. We found that low dose PAF: (a) alters the cytoskeletal structure of intestinal epithelium, (b) causes the influx of FD4 from intestinal lumen to systemic circulation, (c) induces tyrosine phosphorylation of E-cadherin and cadherin-associated proteins. Glucose-induced mucosal permeability increase is abolished by using two structurally different PAF antagonists. 6. These results suggest that endogenous PAF modulates macromolecular movement across the intestinal mucosal barrier, probably via tyrosine phosphorylation of E-cadherin and cytoskeletal alteration of enterocytes.     

Monomorphous histiocytoma in a child. Report of a case with ultrastructural features suggestive of dendritic cell differentiation

The authors describe a rapidly growing soft tissue tumor of predominantly histiocytic composition in an 8-year-old child. The tumor cells were identified as elements of the mononuclear phagocyte system by histologic, histochemical, immunologic, and electron microscopic study. Despite the presence of a minor fibroblastic component, the tumor did not conform to established criteria for a diagnosis of malignant fibrous histiocytoma. Formation of frequent desmosome-like intercellular junctions raised the possibility of dendritic reticulum cell differentiation, since the latter cells seem to be the only elements of the mononuclear phagocyte system that display such specialized cell junctions. The results of immunostaining were discrepant with those reported for normal dendritic reticulum cells, but the currently available information makes it doubtful that the entire neoplastic spectrum of dendritic cell differentiation can currently be diagnosed in surgical pathology.