Adrenal Adenoma

An adrenal adenoma is a growth that develops in the outer layer of one of the adrenal glands, which sit above the kidneys. These growths can occur in adults and are sometimes found by chance during imaging for another health concern. Most are noncancerous, but some produce excess hormones that can affect blood pressure, blood sugar, or other body functions. This adrenal gland tumor is also called an adrenal gland adenoma or adrenal nodule.

Nonfunctioning adenomas often cause no noticeable symptoms and may be discovered unexpectedly on a CT scan or MRI. Symptoms from functioning adenomas depend on which hormone is produced and how much is released. This means adrenal tumor symptoms can vary widely from one person to another.

An adrenal adenoma forms when cells in the adrenal gland grow abnormally. The exact cause is often unknown, and most cases are sporadic rather than caused by a preventable exposure. Diet, stress, or ordinary lifestyle choices usually do not explain why an adenoma develops.

How Hormone Production Affects the Condition

Adenoma cells may release excess cortisol, aldosterone, or sex hormones, so even a small growth can cause health problems. An adenoma is different from other adrenal masses, such as cysts, metastases, or adrenal cancer. Doctors use imaging and hormone tests to help identify which type of adrenal tumor is present.

Most people with an adrenal gland mass did not cause it through diet, exercise, or another lifestyle choice. A family history of adrenal tumors, unusual hormone problems, or an endocrine syndrome may warrant genetic counseling or an endocrine evaluation. Your clinician can decide whether family testing is appropriate based on the pattern of illness and test results.

Complications are uncommon when an adenoma is nonfunctioning and has reassuring imaging features. Problems are more likely when excess hormones remain untreated or when the mass grows or has concerning features. An adrenal tumor may therefore need evaluation even when it is likely benign.

Many adrenal adenomas are discovered incidentally on a CT scan or MRI performed for another reason. Diagnosis combines the mass’s imaging appearance with hormone testing, blood pressure measurements, potassium levels, and the person’s clinical history. This approach helps determine whether the adrenal nodule is benign, hormone-producing, or concerning.

Imaging Tests

An adrenal CT scan or MRI can show the size, shape, density, and internal features of the mass. Clinicians may also assess how quickly contrast leaves the growth, called contrast washout, and whether its size or appearance changes over time. A cyst, metastasis, or another adrenal tumor may have different features and require a different evaluation.

Blood and Urine Hormone Tests

Hormone testing shows whether an adrenal adenoma is functioning, which is one of the most important factors in deciding on treatment. A dexamethasone suppression test is commonly used to check for excess cortisol, while an aldosterone-to-renin ratio can screen for excess aldosterone, especially in people with high blood pressure or low potassium. Plasma or urine metanephrine tests help rule out a pheochromocytoma, a different adrenal tumor that must be identified before any procedure. In selected cases, clinicians may also measure sex hormones or other adrenal hormones, and abnormal results are often confirmed with repeat or additional testing.

Some adenomas only need follow-up, while hormone-producing, enlarging, or suspicious masses may require medication or surgery. The choice depends on imaging, laboratory results, symptoms, overall health, and patient preferences.

Active Surveillance

Active surveillance may be appropriate for a stable, nonfunctioning adenoma with reassuring imaging features. Follow-up can include repeat imaging and, when appropriate, repeat hormone testing or blood pressure checks. A change in size, appearance, symptoms, or hormone production may lead to a different treatment plan.

Medication

Medication may help control the effects of excess cortisol, aldosterone, or other hormones when surgery is not needed or while a treatment plan is being made. It may also be used to manage related problems such as high blood pressure or high blood sugar. Ongoing laboratory monitoring helps the care team adjust treatment safely.

Adrenalectomy

An adrenalectomy removes one adrenal gland and may be recommended for a hormone-producing adenoma, a growing mass, or a lesion with suspicious imaging features. The operation is often performed using minimally invasive techniques, although the approach depends on the mass and the patient’s health. Recovery varies, and hormone testing or temporary hormone replacement may be needed while the remaining adrenal gland adjusts.

Most adrenal adenomas have a favorable outlook, particularly when they are nonfunctioning and have reassuring imaging features. Hormone-producing or indeterminate masses need individualized follow-up to control hormone effects and watch for changes. With appropriate evaluation and treatment, many people maintain good long-term health.

Arrange a medical evaluation if imaging identifies an adrenal mass, or if you have unexplained or difficult-to-control high blood pressure, low potassium, or symptoms suggesting excess cortisol or other hormones. A primary care clinician may arrange testing or refer you to an endocrinologist or adrenal surgeon. Understanding what an adenoma is can help you discuss the right next steps, but testing is needed to determine its significance.