What are the symptoms and causes of Inflammatory Hepatic Adenoma (IHA), a rare benign liver tumor?

From the Guidelines

Inflammatory Hepatic Adenoma is a rare, benign liver tumor characterized by specific symptoms and causes, primarily associated with long-term use of estrogen-containing medications, particularly oral contraceptives, as evidenced by recent studies 1.

Symptoms

The symptoms of Inflammatory Hepatic Adenoma often include:

• Abdominal pain or discomfort in the upper right quadrant
• A palpable mass
• Nausea
• Vomiting
• Occasionally fever Some patients may experience weight loss, fatigue, or malaise. In severe cases, the tumor can rupture, leading to life-threatening intra-abdominal bleeding with sudden severe pain and signs of shock. However, many patients remain asymptomatic, with the tumor discovered incidentally during imaging for unrelated conditions.

Causes

The primary cause of Inflammatory Hepatic Adenoma is long-term use of estrogen-containing medications, particularly oral contraceptives. Women who have used these medications for more than 5 years have a significantly increased risk, as noted in a recent study 1. Other risk factors include obesity, metabolic syndrome, and alcohol consumption. Genetically, these adenomas are associated with mutations in the IL6ST gene, leading to activation of inflammatory pathways.

Diagnosis and Management

The tumors typically show increased inflammatory markers and can be distinguished from other hepatic adenoma subtypes through specific molecular and histological features. Management usually involves discontinuation of oral contraceptives, regular monitoring, and surgical resection for larger tumors due to their higher risk of complications and malignant transformation, as recommended by recent guidelines 1. The use of contrast-enhanced ultrasound for characterization of focal liver lesions, including Inflammatory Hepatic Adenoma, has been established as a valuable diagnostic tool 1.

Key Considerations

It is essential to note that the risk of tumor rupture and hemorrhage is significantly higher in pregnant women with Inflammatory Hepatic Adenoma, particularly those with larger tumors 1. Therefore, close monitoring and management of these patients are crucial to prevent maternal and fetal complications. The most recent study 1 suggests that improvement in clinical outcomes may relate to maternal and fetal outcomes, highlighting the importance of contemporary management strategies.

From the Research

Symptoms of Inflammatory Hepatic Adenoma

• Abdominal pain 2, 3, 4
• Vomiting 2
• Acute anemia 2
• Rupture and hemorrhage 2, 3, 4

Causes of Inflammatory Hepatic Adenoma

• Obesity 2
• Exposure to hormones, particularly oral contraceptive pills 2, 3, 4, 5
• Prolonged use of oral contraceptives 6, 5
• Female sex, with a higher incidence in young women 2, 3, 4, 6, 5
• Genetic factors, with certain subtypes of hepatocellular adenoma having distinct molecular profiles 6

Risk Factors for Complications

• Large lesion size, with tumors larger than 5 cm at increased risk for rupture and malignant transformation 2, 3, 6
• Male sex, with a higher incidence of malignant transformation 6
• Certain molecular subtypes of hepatocellular adenoma, such as the inflammatory or telangiectatic subtype 6