From the Guidelines
An adrenal adenoma is a benign tumor that develops in the adrenal gland, which can be either functioning or non-functioning, and its management depends on whether it is secreting excess hormones and causing symptoms. According to the study published in the Journal of the National Comprehensive Cancer Network 1, adrenal adenomas can cause primary aldosteronism, also known as hyperaldosteronism, which is characterized by elevated plasma levels of aldosterone and low levels of renin activity. The diagnosis of primary aldosteronism involves assessing plasma aldosterone and renin activity, and confirmatory testing with the saline suppression test or salt loading test may be indicated.
Key Characteristics of Adrenal Adenomas
- They are relatively common, affecting a significant portion of the population
- Most are discovered incidentally during imaging tests performed for other reasons
- They can be classified as either functioning or non-functioning
- Functioning adenomas secrete excessive amounts of hormones such as aldosterone, cortisol, or rarely, sex hormones or catecholamines
- Non-functioning adenomas do not produce excess hormones and typically do not cause symptoms
Management of Adrenal Adenomas
- For functioning adenomas, surgical removal (adrenalectomy) is often recommended, typically performed laparoscopically 1
- For non-functioning adenomas smaller than 4 cm with benign imaging characteristics, regular monitoring is usually sufficient
- The distinction between benign adenomas and potentially malignant adrenal masses is important and is based on size, appearance on imaging, and hormone testing
- Adrenal vein sampling for aldosterone is considered the standard for distinguishing between unilateral adrenal adenoma and bilateral adrenal hyperplasia, and should be considered if the patient is a surgical candidate 1
From the Research
Definition of Adrenal Adenoma
- An adrenal adenoma is a type of benign tumor that arises from the cortex of the adrenal gland 2, 3, 4.
- It is the most common benign adrenal tumor, and it can produce excess hormones, such as aldosterone, leading to primary aldosteronism 2, 4.
Characteristics of Adrenal Adenoma
- Adrenal adenomas are typically lipid-rich, meaning they contain a high amount of fat, which can be detected on imaging studies such as CT and MRI 3, 5.
- They can be unilateral or bilateral, and they are usually small, ranging in size from a few millimeters to several centimeters 2, 4.
- Adrenal adenomas can be functional, meaning they produce excess hormones, or non-functional, meaning they do not produce excess hormones 2, 6.
Diagnosis of Adrenal Adenoma
- The diagnosis of adrenal adenoma is typically made using imaging studies such as CT and MRI, which can detect the presence of a tumor and characterize its features 2, 3, 4, 5.
- Other diagnostic tests, such as adrenal venous sampling and dexamethasone suppression testing, may also be used to confirm the diagnosis and determine the functionality of the tumor 2, 4.
- The sensitivity and specificity of CT and MRI for diagnosing adrenal adenoma vary, with MRI being more sensitive and specific than CT in some studies 4.