The adrenal glands are located on top of the kidneys and consist of two parts, the outer layer (cortex) and the inner area (medulla). Some types of adrenal tumors can increase hormonal production (known as functioning tumors). The symptoms of the cancer will depend on whether the tumor is functioning or not, and, if it is functioning, what hormone is being overproduced. Nonfunctioning tumors may cause pain from pressure on abdominal organs, and a mass in the abdomen, which can be felt by pushing with the fingers.

Most adrenal tumors are benign (do not spread) and don’t cause symptoms. They are considered harmless, and aren’t usually treated. Cancerous tumors usually develop in the adrenal cortex, though they can occur in the medulla.

Adrenal cancer is a very rare disease; only approximately 1 or 2 people per million develop it. Prevalence is slightly higher in men than women over the age of 40, and in young children (younger than 5). The cause of adrenal cancer, however, is unknown, and no risk factors have been identified, though heredity plays a role in the development of the disease.