Hepatocellular adenomas are benign tumors of liver closely linked to oral contraceptive and anabolic steroid use that usually involve the right hepatic lobe. Cases have also been described in type I and III glycogen storage diseases and men with metabolic syndrome. Often clinically silent, this condition may be found incidentally or as a result of complications like rupture, hemorrhage or malignant transformation to hepatocellular carcinoma.
Patients may be asymptomatic or may have non-specific complaints if the disease is not complicated, such as abdominal pain that is diffuse or located in the liver projection area or they might notice a palpable mass .
Tumor rupture leads to hemoperitoneum, with various degrees of blood loss, leading to severe abdominal pain accompanied by thirst, tachycardia, hypotension, diaphoresis, signs of hypovolemic shock. If left untreated, this complication causes death.
Jaundice appears if the biliary duct is compressed by the tumor, and this happens more often if several hepatocellular adenomas coexist. Some patients may present with pallor and asthenia, symptoms of chronic anemia. If malignant transformation occurs, symptoms resemble those of hepatocellular carcinoma , such as weight loss, pruritus, encephalopathy symptoms, splenomegaly, variceal bleeding, increasing abdominal girth due to ascites.
Clinical examination should look for direct tumor symptoms (right hypochondrium mass or hepatomegaly), acute or chronic bleeding signs (tachycardia, orthostatic or permanent hypotension, pallor), compression signs (jaundice) and indications for tumor rupture: severe abdominal pain with peritoneal signs or fluid wave sign.
Blood workup should include the determination of aspartate aminotransferase, alanine aminotransferase (likely to be elevated due to the compression exerted by the tumor on the rest of the hepatocytes), gamma-glutamyl transferase and alkaline phosphatase, that might also be mildly elevated, complete blood cell count and inflammatory markers such as C-reactive protein and serum amyloid A that might also be high, alpha-fetoprotein that should be normal (if abnormal, consider carcinoma), carcinoembryonic antigen (if high, consider colon metastasis) and entamoeba histolytica and echinococcus granulosus tests.
Abdominal ultrasonography describes a well delineated, hypoechoic mass with venous flow patterns, better described by contrast-enhanced echography . Computer tomography (CT) and magnetic resonance imaging (MRI) scans may describe necrosis and calcification.
Classic histology techniques performed on a needle aspiration specimen may be non-diagnostic (usually showing normal hepatocytes with abnormal lobular arrangement or peliosis hepatis), but immunohistochemistry may be useful: glutamine synthetase staining , E-cadherin, matrix metalloproteinases 1, 2, 7 and 9 , agrin and CD 34 , glycipan-3  and cytokeratin 7 and 9  may be valuable markers. Still, percutaneous biopsy of a presumed hepatocellular adenoma should not be routinely performed, as it might induce bleeding and dissemination. Immunohistochemical techniques can also be applied to excised masses if there is doubt about their nature.
Tc99m sulfur colloid scans show a photopenic center with a high uptake rim or a homogenous high uptake lesion . Angiographic studies describe a well-irrigated periphery, different from the pattern seen in focal nodular hyperplasia .