What are the adrenal glands?
- The adrenal glands are small glands that are located just above each kidney (they are sometimes called the suprarenal glands for that reason). They are triangular in shape and consist of several distinct parts:
- The central part of the gland is called the adrenal medulla and produces the chemicals epinephrine (also called adrenaline) and norepinephrine. Both of these chemicals are involved in regulation of the nervous system.
- The outside part of the gland surrounding the medulla is the adrenal cortex. This part of the adrenal gland is largely responsible for producing steroid hormones in the body.
What are adrenal tumors, and what types of adrenal tumors are there?
- Normally, cells in the body will grow and divide to replace old or damaged cells. This growth is highly regulated, and once enough cells are produced to replace the old ones, normal cells will stop dividing. Tumors occur when there is an error in this process, and cells continue to grow in an uncontrolled manner.
- Tumors can either be benign or malignant. Although benign tumors can grow in an uncontrolled way, they do not spread to other parts of the body (metastasize), nor do they invade surrounding tissues. Malignant tumors (also known as cancers) will grow uncontrolled in such a way that they invade and damage other tissues around them. They also gain the ability to break off from where they start and spread to other parts of the body, usually through the blood stream or through the lymphatic system where the lymph nodes are located (a process known as metastasis).
What are the signs of adrenal cortical tumors?
- Both adrenal adenomas and adrenal cortical cancers can produce excess steroid hormones. Symptoms vary depending on the steroid that is produced. If too much aldosterone, which is a type of steroid hormone, is produced, Conn’s syndrome (also known as primary hyperaldosteronism) can develop. Conn’s syndrome most commonly occurs with pituitary adenomas, but it can also occur in the setting of adrenal hyperplasia (an overgrowth of normal adrenal cortical tissue) and adrenal cortical cancers. Signs of Conn’s syndrome include elevated blood pressure, decreased levels of potassium in the blood, and decreased levels of a chemical produced by the kidneys called renin in the blood. In most cases of Conn’s syndrome, elevations in blood pressure are mild to moderate.
What causes adrenal cortical cancers?
- In general, causes of adrenal cortical cancers are unknown. They are not associated with smoking, and do not run in families. Despite this, certain genetic mutations have been associated with adrenal cortical cancers, and research is ongoing in attempt to identify the causes of these cancers.
How are adrenal cortical cancers diagnosed, and how do you tell them apart from adrenal adenomas?
- Functioning adrenal cortical cancers and adenomas are frequently diagnosed because of the symptoms caused by steroid hormones. Patients with Cushing’s syndrome need to be evaluated to see if the syndrome is caused by a problem in the adrenal glands, the pituitary gland, or another tumor somewhere else in the body. The first step is measuring the amount of cortisol in the urine (called a 24-hour urinary free cortisol test). This test is sometimes performed while giving the patient an extra dose of steroids to see how the body responds. After this is done, most patients undergo a dexamethasone suppression test where patients are given a high dose of the steroid dexamethasone.
How are adrenal cortical cancers staged?
- Stage I: The cancer is smaller than 5 cm and has not spread outside of the adrenal gland.
- Stage II: The cancer is larger than 5 cm and has not spread outside of the adrenal gland.
- Stage III: The cancer has spread into the fat surrounding the adrenal gland or has spread to lymph nodes or other organs near the adrenal gland.
How are adrenal treated?
- Most adrenal adenomas are detected on a CT scan or MRI scan that is performed for an unrelated reason. It is only necessary to treat them if they are causing symptoms. Otherwise, they can be followed with repeated scans periodically. In the event that an adenoma does need to be treated, surgical removal is the most frequent treatment used. In many cases, this can be performed using a laparoscopic procedure. A laparoscope is a small fiberoptic camera that can be inserted into the abdomen through small incisions. Other small instruments can also be inserted through these incisions. The adrenal adenoma can be resected while inside the body, without making a large incision in the abdomen, and removed through the small holes through which the camera and other instruments are inserted.
- Currently, the only known way to cure adrenal cortical cancers is complete surgical removal of the tumor. Unfortunately, this is only possible for some patients with this disease. At least half of patients with adrenal cortical cancers have metastases or cancer invading into other organs, so that complete removal of the tumor is not possible. The best results with surgical resection have been with an en bloc resection, meaning that the entire tumor is removed in one piece. This also includes removing the entire kidney on the same side as the adrenal cancer. Because of this, it is unusual for adrenal cancers to be removed using a laparoscopic procedure, although as techniques of laparoscopic resection improve, more patients are being treated with this method. Occasionally, adrenal cancers will grow into the large blood vessel that carries blood back from the lower body to the heart (the vena cava). Even in these cases, complete removal of the cancer can sometimes be performed, but will require input from a general surgeon, an urologist, and a vascular surgeon.
- Chemotherapy refers to a group of medications that are given intravenously or orally as a pill. These drugs travel throughout the body to kill cancer cells. This is one of the big advantages of chemotherapy. If cancer cells have broken off from the tumor and are somewhere else inside the body, chemotherapy has the chance of killing them. A number of different chemotherapeutic agents exist, each with its own side effects. You should discuss the potential side effects of any chemotherapy you may receive with your medical oncologist.
- Radiation therapy is used in a number of cancers as both the main method of killing cancer cells or in combination with surgery (either before or after). The radiation comes in the form of high-energy x-rays that are delivered to the patient only in the areas at highest risk for cancer. These x-rays are similar to those used for diagnostic x-rays, only of a much higher energy. The high-energy of x-rays in radiation therapy results in damage to the DNA of cells, causing tumor cells to die.
Other Drug Treatments
- Patients who are treated for adrenal cortical cancers may have symptoms that are due to levels of hormones that are either too high or too low. Physicians may recommend other medications, such as ketoconazole or metyrapone, to treat these symptoms.