Hepatocellular Adenoma, Liver, Rat

Abstract

Hepatocellular adenomas vary in size and multiplicity. Most are nonfatal and are discovered incidentally when animals are killed or die for other reasons. If a liver tumor is located close to the ventral body wall, it may be detectable by palpation in a nonobese animal. However, this is not a reliable way to detect liver tumors in living animals. Moreover, since heavy palpation may cause a tumor to bleed, this method of detecting liver tumors in living animals is not recommended. If an adenoma arises near the liver surface, it may be noticed at necropsy even though it has a mean diameter of less than a millimeter. Otherwise the presence of small adenomas may not be suspected until tissues are trimmed after fixation or until sections are examined under the microscope. Even the presence of a very larger tumor that replaces and expands a whole lobe of the liver may not be suspected until necropsy unless it gives rise to abdominal distension.