What is adrenal adenoma?

Adrenal adenomas are tumors that are typically benign and asymptomatic. They are found in the adrenal glands, which are located on top of the kidneys. The main function of these glands is to produce hormones that help regulate blood pressure, manage stress, develop sex organs, and control puberty. Adrenal adenomas can appear at any stage of life, though they are more common in young children and adults between 40 and 50 years old.

Adrenal Tumor

Clinical studies suggest that benign adrenal adenomas may be caused by a problem in another gland or when a disease or infection affects one or both of the adrenal glands. It can also be caused by macronodular hyperplasia, a condition in which the adrenal glands enlarge and produce larger amounts of cortisol.

Adrenal adenomas generally do not cause problems or symptoms, but in some cases, the excessive presence of certain hormones can lead to complications.

The hormones most frequently secreted in excess are:

• Aldosterone: A hormone that regulates the balance of sodium and potassium, helping to control blood pressure.
• Cortisol: The stress hormone that influences metabolism, inflammation, and the body’s immune response.
• Adrenaline: A hormone that prepares the body to react to danger, increasing heart rate and energy.

Benign adrenal adenomas are typically asymptomatic tumors that are discovered incidentally during imaging studies performed for other reasons, which is why they are known as “incidentalomas.” However, if they are functional, meaning they produce hormones in excess, they can generate specific symptoms depending on the affected hormone.

For example, if the tumor secretes cortisol, it can cause Cushing’s syndrome with symptoms like weight gain in the trunk, a rounded face, muscle weakness, or thin skin. If it produces aldosterone, it can present with difficult-to-control high blood pressure, weakness, cramps, and low potassium levels.

Although rare, if they secrete androgens or estrogens, they can cause signs of masculinization or feminization, respectively.

On the other hand, malignant adenomas, such as adrenal carcinoma, tend to cause more obvious and aggressive symptoms. These types of tumors can also be functional, but their most characteristic features are rapid growth, unexplained weight loss, and general malaise.

In this type of malignant tumor, hormone production is often mixed and disordered, complicating the clinical picture with multiple overlapping endocrine symptoms. In advanced stages, symptoms related to metastasis, such as bone pain or respiratory symptoms, may appear.

The diagnosis of an adrenal adenoma usually begins with imaging studies like magnetic resonance imaging (MRI) or computed tomography (CT) scans. These studies help identify the presence, size, and characteristics of the nodule in the adrenal gland.

Benign lesions are typically less than 4 centimeters, homogeneous, and have well-defined borders. However, lesions larger than 4 centimeters, irregular, or with atypical characteristics, often raise suspicion of malignancy and require a more detailed evaluation.

Once an adrenal adenoma is detected, it’s essential to determine if it is functional. This is done by requesting hormonal studies of the blood and urine, which help detect cortisol, aldosterone, renin, catecholamines, metanephrines, and sex hormones. These tests can identify if the tumor is producing an excess of one or more hormones.

If the imaging study is inconclusive or malignancy is suspected, a biopsy may be considered, although it’s used with caution due to the risk of spreading tumor cells or affecting tumors that produce catecholamines.

The treatment for adrenal adenomas will vary depending on whether they are functional or not, as well as their radiological characteristics.

For benign, non-functional adenomas that measure less than 4 centimeters, immediate intervention is generally not required. However, they do require monitoring with periodic imaging and hormonal evaluations to rule out growth or the development of functional activity.

In the case of a functional adenoma, regardless of its size, the recommendation is to surgically remove it via an adrenalectomy, which is usually performed laparoscopically.

For adenomas suspected of malignancy or for adrenocortical carcinomas, the main treatment is also surgery. In this case, a wider resection is required with a curative intent if there is no metastasis.

Afterward, adjuvant treatment with mitotane may be indicated, and in some cases, radiotherapy or chemotherapy, depending on the stage and progression of the tumor.

Follow-up is mandatory, as these tumors have a high recurrence rate and can severely affect the patient’s hormonal balance.

At the Internal Medicine department and the Cancer Center at ABC Medical Center, we can provide you with specialized care. Contact us!