Giant infantile hemangioendothelioma of the liver. Scintigraphic diagnosis.

Infantile hemangioendothelioma of the liver is benign mesenchymal tumor composed of anastomosing vascular channels lined with plump endothelial cells. It is a congenital lesion noted at birth or during the first 6 months of life. The authors report a large infantile hemangioendothelioma that was imaged with anatomical modalities and Tc-99m RBC scintigraphy. An early "blush" on Tc-99m RBC hepatic scintigraphy is a diagnostic feature of infantile hemangioendothelioma.

Spontaneous rupture of the spleen due to acquired immunodeficiency syndrome in an intravenous drug abuser.

A case of spontaneous rupture of the spleen is described in a 25-year-old woman with a history of intravenous drug abuse. At autopsy the spleen and the lymph nodes were soft, slightly enlarged, and markedly congested. They showed reactive follicular hyperplasia with increased cellularity and prominent vascularity of the red pulp and the interfollicular tissue. The postmortem serum was positive for antibodies to human T-cell lymphotropic virus type III. Other serologic tests were negative, including heterophile antibody test, test for antibodies to Epstein-Barr virus, and toxoplasmosis.

B-cell lymphomas morphologically resembling T-cell lymphomas.

Seven cases of B-cell lymphoma that morphologically resembled T-cell lymphoma are described. These cases are of four morphologic types: atypical poorly differentiated lymphocytic lymphoma (PDLL) with convoluted nuclei, "Lennert's" lymphoma, mixed lymphocytic-"histiocytic" lymphoma with large variation in size of abnormal cells, and "histiocytic" lymphoma with large multilobed nuclei. These cases add further support to the belief that morphologic criteria alone are not sufficient for accurate immunologic classification of the malignant lymphomas since they may represent a distinct clinicopathologic entity.

Effect of dietary fiber on azoxymethane-induced intestinal carcinogenesis in rats.

The effect of alfalfa, bran, and cellulose on intestinal tumor formation and fecal billary steroid levels was studied in male Sprague-Dawley rats given injections of azoxymethane (AOM). Animals received weekly injections of 8 mg AOM/kg and were fed diets containing 10% fiber (wt/wt) and 35% beef fat or 20 or 30% fiber and about 6% beef fat. Control animals in each instance were fed fiber-free diets. The addition of 10% fiber to the high-fat diet did not significantly reduce the intestinal tumor frequency (average No. of tumors/rat). However, addition of 20 or 30% fiber to the 6% fat diet significantly reduced the intestinal tumor frequency. The concentration of fecal biliary steroids (mg/g dry feces) was significantly lowered in the groups with reduced tumor frequencies, whereas the total excretion of fecal biliary steroids (mg/day) did not show a similar correlation. These observations suggest that intestinal tumor frequency can be reduced by increased dietary fiber only when fat intake is not at a high level. The effect of fiber may be due to dilution of promoters and/or carcinogens in the intestinal tract.