The liver is an organ in the abdominal cavity that has many important functions, including filtering blood from the intestines, secreting bile to aid in digestion, metabolizing drugs, and synthesizing proteins. The liver's vascular system, location, and functions make it susceptible to a number of conditions that lead to hepatomegaly, defined as enlargement of the liver beyond its normal size. Hepatomegaly may be suspected based on the results of a physical exam or imaging studies of the liver.