Adrenal glands, small organs located atop each kidney, produce hormones essential for regulating various bodily functions. Sometimes, benign (non-cancerous) growths, known as adrenal adenomas, can form within these glands. These growths are a common type of adrenal gland tumor, often found incidentally during medical imaging for other conditions. While the term “tumor” might sound concerning, most adrenal adenomas are harmless and do not cause symptoms or require treatment.
What Are Adrenal Adenomas?
Adrenal adenomas originate from the adrenal cortex, the outer part of the adrenal gland. This part of the adrenal gland produces steroid hormones, including cortisol, aldosterone, and small amounts of sex hormones. Adrenal adenomas are categorized based on their hormonal activity.
Non-functional adenomas do not produce excess hormones and typically remain asymptomatic. Functional adenomas, conversely, secrete an overabundance of specific hormones, leading to various health effects. The most common hormones overproduced by functional adenomas are cortisol and aldosterone. Cortisol helps the body manage stress, regulate metabolism, and control blood pressure; excessive production can lead to Cushing’s syndrome. Aldosterone helps regulate blood pressure and balance salt and potassium levels; an overproduction can cause primary aldosteronism, also known as Conn’s syndrome.
Symptoms and Diagnosis
Non-functional adrenal adenomas typically do not cause symptoms. For functional adenomas, however, symptoms arise directly from the excess hormone production.
Excess cortisol from an adenoma can lead to Cushing’s syndrome, characterized by symptoms such as weight gain (particularly around the abdomen and face), a fatty hump between the shoulders, thinning skin, easy bruising, purple stretch marks, muscle weakness, fatigue, high blood pressure, and elevated blood sugar levels. Mood changes, like anxiety or depression, can also occur. An overproduction of aldosterone causes primary aldosteronism. The primary symptom is often high blood pressure that can be difficult to manage, even with medication. Low potassium levels, which can result from excess aldosterone, may lead to muscle weakness, muscle cramps, fatigue, increased thirst, and frequent urination.
Diagnosing adrenal adenomas involves a combination of imaging and hormonal tests. Imaging tests, such as computed tomography (CT) scans or magnetic resonance imaging (MRI), are commonly used to locate the adenoma and assess its characteristics, helping determine if the tumor is likely benign. Blood and urine tests measure hormone levels, such as cortisol and aldosterone, to determine if the adenoma is functional, with a 24-hour urine collection often used for cortisol. A biopsy is rarely considered, only if malignancy is suspected or imaging results are unclear.
Treatment and Outlook
The approach to managing an adrenal adenoma depends largely on whether it is functional, its size, and if it is causing symptoms. For small, non-functional adenomas that do not produce hormones, observation, often called “watchful waiting,” is a common strategy. This involves periodic monitoring with imaging and hormone tests to ensure the adenoma does not grow significantly or become hormonally active.
If an adenoma is functional and producing excess hormones, treatment is typically recommended to address the hormonal imbalance and associated symptoms. Medications can be prescribed to either block the effects of the excess hormones or reduce their production; for instance, drugs like spironolactone can counteract the effects of high aldosterone. Surgical removal of the affected adrenal gland, known as an adrenalectomy, is a definitive treatment option. This procedure is often recommended for adenomas that are causing significant symptoms due to hormone overproduction, for larger adenomas (generally over 4 centimeters), or if there is any concern about malignancy. Laparoscopic surgery, a minimally invasive technique, is frequently used for benign adrenal adenomas.
The prognosis for most individuals with adrenal adenomas is generally favorable. Successful treatment, especially for functional adenomas, can resolve or significantly improve related symptoms like high blood pressure and other metabolic issues. Regular follow-up with healthcare providers is important to monitor the adenoma and manage any ongoing health concerns.