Focal Carcinoma in Hepatocellular Adenoma, Liver, Mouse

Hepatocellular adenomas (Figs. 82, 83) in the mouse are seen as sharply demarcated, roughly spherical, nonencapsulated masses that may reach a diameter of 1.5 cm. They usually elevate the hepatic capsule and thus project from the surface of the liver. Some of these masses may have a yellowish tint due to the presence of fat in the cells (Fig. 82); others are somewhat less dark than the adjacent liver (due to the presence of basophilic and clear cells (Fig. 83), and still others may closely resemble the color and pattern of the liver (Fig. 84). The hepatocellular carcinomas occasionally found within an adenoma are not usually recognized grossly, although some may be seen at low magnification (Fig. 84). These carcinomas are more apt to be found in adenomas which exceed 1 cm in diameter.