Types of adrenal gland tumours

Adrenal gland tumours can be cancerous or non-cancerous. A cancerous (malignant) tumour can grow into and destroy nearby tissue. It can also spread (metastasize) to other parts of the body. A non-cancerous (benign) tumour does not spread to other parts of the body and is not usually life-threatening. Most adrenal gland tumours are non-cancerous.

Adrenal gland tumours are grouped as functional and non-functional. Functional tumours make too much of certain hormones and cause symptoms. Non-functional tumours usually don’t make any hormones and don’t cause symptoms.

A cancerous tumour that spreads to an adrenal gland from another part of the body is called secondary adrenal gland cancer. It is different than primary adrenal gland cancer, which is when the cancer starts in an adrenal gland. Secondary adrenal gland cancers are more common than primary adrenal gland cancer. They include melanoma, lymphoma and cancers of the lung, breast, colon and rectum.

Adrenocortical carcinoma (ACC) is the most common primary adrenal gland cancer. It is also called adrenal cancer or adrenal cortical cancer. It starts in the outer layer of the adrenal gland (adrenal cortex). Tumours are usually larger than 6 cm in diameter.

ACC is often found when it produces hormones that cause changes in the body or when the tumour causes symptoms because it has become very large. Sometimes it is found when imaging tests are done for other health reasons.

About 60% of ACCs are functional tumours. With ACC, the adrenal gland produces too much of a certain type of hormone. The most common hormone overproduced by ACC is cortisol. Other hormones that may be overproduced are aldosterone, androgens and estrogen.

ACC appears slightly more often in females than males. It affects the right adrenal gland more often than the left.

A pheochromocytoma is a tumour that starts in the inner layer (medulla) of the adrenal gland. Most pheochromocytomas are non-cancerous, but some may be cancerous.

Pheochromocytomas start in the chromaffin cells of the adrenal medulla. These cells look like nerve cells but produce hormones like endocrine cells. Most pheochromocytomas are functional tumours and produce too much of the hormones epinephrine and norepinephrine (called catecholamines).

Pheochromocytomas occur most often between the ages of 29 and 50, and they occur equally in men and women. Pheochromocytomas are rarely seen in children. They are usually found in one adrenal gland, but they sometimes occur in both adrenal glands or in more than one area at the same time.

A small number of pheochromocytomas start in the chromaffin cells outside the adrenal medulla. These are called extra-adrenal pheochromocytomas or paragangliomas. They occur most often in the abdomen. They are more likely to be cancerous than pheochromocytomas that start in the adrenal gland.

Neuroblastoma is a type of cancer that starts in immature nerve cells (neuroblasts) of the sympathetic nervous system. The sympathetic nervous system prepares the body for situations where you need strength and awareness, such as those that cause fear, anger, excitement or embarrassment.

Neuroblastoma can develop anywhere in the sympathetic nervous system, but it starts most often in the adrenal gland.

Neuroblastoma most commonly develops in babies and young children. It is the most common solid tumour outside of the brain in children. It accounts for 8% to 10% of all cancers in children.

Find out more about neuroblastoma.

An adrenal adenoma is a non-cancerous tumour that starts in the outer layer of the adrenal gland. Adrenal adenomas are the most common type of adrenal gland tumour. They are often found when an imaging test of the abdomen is done for other health reasons.

If the adrenal adenoma remains small and is non-functional, treatment may not be needed. If treatment is done, treatment options include:

• observing the growth of the adenoma with CT scans
• checking for changes in hormone levels with lab tests

If the adenoma is functional, treatment options include:

• surgery to remove the adrenal gland that contains the adenoma
• drugs that block the hormones made by the tumour
• drugs that control symptoms due to too much production of certain hormones – this may be used for people who cannot have surgery because of other health problems