Hepatocellular adenoma

What is a hepatocellular adenoma?

A hepatocellular adenoma (HCA) is a rare, non-cancerous tumor that grows directly from your main liver cells. They affect about 3 in 100,000 people and are most common in women of reproductive age.

HCAs are classified by their molecular subtype, which has important implications for malignancy risk and management:

• HNF1A-Inactivated HCA: the most common type (35% to 40%). It is strongly linked to using birth control pills and carries a very low risk of becoming cancerous.

• Inflammatory HCA: accounts for 40% to 50% of cases and is linked to obesity, alcohol use, and metabolic issues. It has a higher risk of bleeding and a moderate risk of turning cancerous.

• Beta-catenin activated HCA: accounts for 10% to 15% of cases. This type has the highest risk of turning into liver cancer. It is more common in men and is linked to anabolic steroid use.

• Unclassified HCA: a rare catch-all category for tumors that do not fit into the other groups and require close monitoring.

Why size and type matter: larger HCAs, particularly those above 5 cm, have a greater risk of haemorrhage and are more likely to require active management. Doctors use the specific tumor type and size to decide whether it is safe to just monitor the lump or if it needs to be surgically removed.

Symptoms of hepatocellular adenomas

Many hepatocellular adenomas cause no symptoms and are discovered entirely incidentally on abdominal imaging. When symptoms occur they reflect tumour size, location, or complications:

• A dull aching discomfort or heaviness in the upper right abdomen from the mass itself

• Acute severe right upper abdominal or generalised abdominal pain from spontaneous haemorrhage into or around the tumour, which can be life-threatening in large lesions

• Nausea and early satiety from compression of adjacent structures by large tumours

• A palpable abdominal mass in large lesions

• Symptoms of acute haemoperitoneum including shoulder tip pain, hypotension, and shock in the rare event of capsule rupture and intraperitoneal bleeding

What causes hepatocellular adenomas?

HCAs develop from molecular alterations in hepatocyte proliferation and differentiation, strongly influenced by hormonal and metabolic factors. Contributing causes include:

• Oral contraceptive pill use is the most strongly established risk factor, with long-term oestrogen exposure driving hepatocyte proliferation. Risk increases significantly with duration of use and oestrogen dose. HCA may regress with cessation of oral contraceptives.

• Anabolic steroid use is the most important risk factor in men, driving beta-catenin activated HCA with the highest malignancy risk.

• Obesity and metabolic syndrome are associated with inflammatory HCA through hepatic steatosis and chronic low-grade inflammation.

• Alcohol excess is associated with inflammatory HCA development.

• Glycogen storage diseases particularly types Ia and III, are associated with multiple HCAs and a higher risk of malignant transformation.

• HNF1A gene mutations cause hepatic adenomatosis, a rare condition of multiple liver adenomas, through germline HNF1A inactivation.

• Male sex while HCA is predominantly a condition of young women, men who develop HCA have a higher proportion of beta-catenin activated subtype and consequently higher malignancy risk.

How is a hepatocellular adenoma detected?

Hepatocellular adenomas are detected through abdominal MRI, with blood tests assessing liver function, hormonal context, and markers relevant to malignant transformation.

Abdominal MRI Elfcare’s full body MRI maps your liver and can suggest the likely subtype of a hepatocellular adenoma based on its distinct signal pattern, often without needing an invasive biopsy. In some cases, particularly when the imaging findings are ambiguous or a higher-risk subtype is suspected, a biopsy may still be recommended to confirm the diagnosis.

Blood tests assess liver function, hormonal context, and markers relevant to the conditions most closely associated with HCA development. Relevant markers in Elfcare's panel include:

• ALT, AST, GGT, ALP, and bilirubin comprehensive liver function assessment, relevant to identifying coexisting liver disease and monitoring treatment response

• Albumin reflects liver synthetic function and overall hepatic health

• HbA1c and glucose assess metabolic health, relevant to the obesity and metabolic syndrome association with inflammatory HCA

• Triglycerides and lipid profile metabolic context for inflammatory HCA associated with hepatic steatosis

• Oestradiol and progesterone hormonal assessment relevant in women taking oral contraceptives, where cessation may be recommended following HCA diagnosis

• Testosterone relevant in men, where anabolic steroid use is the primary risk factor for the highest-risk beta-catenin activated subtype

• CRP systemic inflammation relevant to inflammatory HCA and monitoring disease activity

• Haemoglobin and haematocrit assess for anaemia from chronic bleeding or acute haemorrhage from the lesion

Why early detection matters

Identifying a hepatocellular adenoma allows its size, characteristics, and risk factors to be assessed before complications develop. Management may include stopping relevant hormonal exposure, addressing associated metabolic factors, and monitoring the lesion with interval imaging. Some adenomas decrease in size after oral contraceptives are stopped or after significant weight loss. Cessation of the oral contraceptive pill leads to regression in a proportion of HNF1A-inactivated adenomas. Weight loss reduces the inflammatory driver of inflammatory HCA. These interventions are only available when the tumour is identified before it has grown large enough to cause complications. Large HCAs above 5 cm carry a significant spontaneous haemorrhage risk, and elective surgical resection or ablation under controlled conditions is considerably safer than emergency surgery for a ruptured tumour causing haemoperitoneum. Beta-catenin activated HCAs identified early can be resected before malignant transformation to hepatocellular carcinoma, which, once established, carries a dramatically different prognosis.

How Elfcare can help

Elfcare's full body MRI images the liver directly as part of the standard abdominal sequence, identifying hepatic lesions and providing the MRI characterisation needed to distinguish HCA from other liver masses including haemangioma, focal nodular hyperplasia, and hepatocellular carcinoma.

Our blood panel complements imaging by assessing liver function and metabolic health. These results can provide useful clinical context when a liver lesion is identified and may highlight other findings that warrant further assessment.

If our MRI or blood tests identify a hepatocellular adenoma or a liver lesion requiring further characterisation, we take care of further diagnostics or refer you to the appropriate specialist.