Adrenal Adenoma

Excerpt

Adrenal adenomas are benign neoplasms that originate from the adrenal cortex. Most adrenal adenomas are typically discovered incidentally during abdominal imaging, leading to the monicker “adrenal incidentaloma.” The significance of adrenal adenomas lies in their potential hormonal activity. Although many adrenal adenomas do not produce any hormones, these adenomas can overproduce adrenal cortical hormones.

The adrenal glands, situated superiorly to the kidneys, produce hormones. They consist of both medullary and cortical tissues. The adrenal medulla, which accounts for approximately 15% of the adrenal mass, responds to circulating dopamine during stressful situations by producing and releasing catecholamines as part of the sympathetic stress response. The adrenal cortex can be subdivided into distinct regions known as the zona glomerulosa, zona fasciculata, and zona reticularis. Each zone is responsible for producing specific hormones, namely mineralocorticoids, glucocorticoids, and androgens, respectively.

When a mass is detected within the adrenal gland, either incidentally or due to symptoms, it is crucial to differentiate between benign and malignant masses and functional and nonfunctional masses. This comprehensive evaluation process is essential not only for accurate identification but also for excluding potentially life-threatening malignancies.

Adrenocortical carcinoma and pheochromocytoma represent potentially malignant masses that can occur in the adrenal glands. Although these tumors may exhibit hormonal activity, they differ from adenomas in their ability to expand and metastasize beyond the adrenal gland, potentially leading to metastasis.

Adrenal adenomas, in contrast, do not possess the potential to become malignant. Adenomas that do not produce hormones (nonfunctional) and are small in size do not require additional treatment. However, when an adenoma produces adrenal cortical hormones, it often involves cortisol or aldosterone. Androgen-producing adenomas are extremely rare and are more often associated with adrenocortical carcinoma. Excess cortisol production can be classified based on the amount of hormone produced and the associated symptoms. Adenomas that produce cortisol associated with systemic symptoms are considered typical presentations of Cushing syndrome. On the other hand, adenomas that produce cortisol in smaller quantities, without obvious signs of hypercortisolism, are referred to as mild autonomous cortisol secretion (MACS) tumors. The treatment approach for adrenal adenomas involves managing the hormonal imbalance and considering surgical correction.