The adrenal gland consists of the adrenal cortex and the adrenal medulla.
Various hormones, the so-called steroid hormones, are produced in the adrenal cortex. These include
- Glucocorticoids (the main representative is cortisol),
- mineralocorticoids (the main representative is aldosterone) and
- sex hormones.
The so-called catecholamines (adrenaline, noradrenaline and dopamine) are produced in the adrenal medulla.
Malignant glandular tumors are called carcinomas. Tumors of the adrenal gland can be accompanied by increased hormone production. This can lead to various clinical pictures that may make an adrenalectomy necessary.
Adrenalectomy may be necessary for two reasons:
- For hormone-producing tumors of the adrenal gland
- In the case of malignant tumors of the adrenal gland or suspected malignant tumors.
The adrenal gland sits in a pyramid shape on the actual kidney © Peakstock | AdobeStock
Adrenalectomy for overproduction of glucocorticoids
The overproduction of glucocorticoids leads to Cushing's syndrome. This disease causes significant changes in affected patients.
Symptoms of Cushing's syndrome
It leads to
- a redistribution of body fat with an emphasis on the trunk (truncal obesity),
- a strikingly round facial shape (full moon face) and
- in many cases, an increase in fatty tissue in the neck area (buffalo neck).
Striae rubrae, which are reddish stretch marks on the skin, are also characteristic. They can appear
- on the trunk,
- on the thighs and
- on the upper arms
can occur.
In women there is an
- increase in facial hair and
- possibly a certain amount of breast hair (so-called hirsutism).
Irregularities in the menstrual cycle, including amenorrhea, are also typical of this clinical picture.
The skin becomes noticeably thin and sensitive, and bleeding often occurs.
Other typical symptoms of Cushing's syndrome are
Cushing's syndrome is a serious disease. If it remains untreated, it leads to death in 50% of patients within 5 years.
Causes of Cushing's syndrome
Cushing's syndrome is usually triggered by a tumor of the pituitary gland (pituitary tumor). This stimulates the adrenal gland to produce more glucocorticoids. The second most common cause is a tumor of the adrenal gland itself, which can be benign or malignant.
In very rare cases, tumors of other organs are the cause, e.g. small cell bronchial carcinomas. They produce a protein that is similar to the stimulating hormone of the pituitary gland. It can also stimulate the adrenal glands to produce more glucocorticoids. This is referred to as a paraneoplastic cause of Cushing's syndrome.
If possible, a pituitary tumor is removed by means of neurosurgery. If this is not possible, an adrenalectomy is considered as a last resort.
The same applies to the paraneoplastic cause of increased hormone production. The adrenal gland should be removed if it harbors a tumor that causes Cushing's syndrome.
Adrenalectomy for overproduction of mineralocorticoids
The increased production of aldosterone leads to Conn's syndrome. The overproduction of aldosterone causes less sodium to be excreted via the kidneys. Instead, more potassium is released into the urine.
The excessive sodium content in the body binds water. This increases the volume of fluid in the bloodstream. This leads to high blood pressure, which is often difficult to control. Many patients therefore need three or more different blood pressure medications.
If high blood pressure is difficult to control combined with potassium deficiency, doctors should consider diagnosing Conn's syndrome. However, there are also a number of patients who do not have low potassium levels.
The increased production of aldosterone can be caused by bilateral adrenal cortical hyperplasia. This means that both adrenal glands are equally involved in the increased aldosterone production. In these cases, drug therapy with an aldosterone antagonist is the treatment of choice.
If the hormone overproduction is caused by a unilateral adrenal tumor, an adrenalectomy should be considered. These are often very small tumors. It is therefore sometimes advisable to determine in which adrenal gland the increased hormone production is taking place. This can be found out by determining the hormone levels in the blood.
Adrenalectomy for overproduction of sex hormones
An overproduction of sex hormones is usually only noticeable when opposite-sex hormones are produced.
If the female body produces too much testosterone, male hair develops with
- beard growth,
- hair on the chest and
- formation of a receding hairline.
Physique and facial features can also become very masculine.
Men with estrogen-producing tumors may experience breast growth (gynecomastia). Libido is also usually reduced.
Testosterone-producing tumors are common, estrogen-producing tumors are almost always malignant.
Adrenalectomy for catecholamine-producing tumors
Tumors of the adrenal medulla are called pheochromocytomas. They release an increased amount of catecholamines, i.e.
- adrenaline,
- noradrenaline
- and dopamine.
These hormones increase blood pressure and cardiac output. An increased and uncontrolled release of these hormones can therefore lead to life-threatening blood pressure crises.
A characteristic symptom of these tumors is therefore high blood pressure. This can be permanently high. However, episodes of high blood pressure, known as hypertensive crises, are typical. These are often accompanied by
If the tumor has not yet been diagnosed, these patients are particularly at risk in stressful situations, such as
- traffic accidents,
- childbirth or
- operations.
Adrenalectomy for malignant adrenal tumors
Adrenocortical carcinoma is a rare tumor with a poor prognosis. Early detection of the tumor is therefore of the utmost importance.
Malignant adrenal tumors are usually relatively large at the time of diagnosis. The larger a tumor is, the greater the risk that it is malignant. For this reason, almost all adrenal tumors larger than 4 to 5 cm should be removed. Exceptions are adrenal cysts and so-called angiomyelolipomas.
If CT or MRI shows that the suspicious tissue contains little fat, the suspicion of a tumor increases. By injecting a contrast agent into the vein, a CT scan can show how a tumor is flooded in and out. This can also indicate whether the tumor is benign or malignant. In this way, even smaller tumors can be identified as suspected carcinomas.
Around half of adrenocortical carcinomas lead to increased hormone production. Tumors that produce increased amounts of cortisone or testosterone are often carcinomas. Tumors that produce an increased amount of oestrogen or release an increased amount of various hormones are almost always malignant.
Metastases of other tumors often form in the adrenal glands. This means that primary tumors, such as
- bronchial carcinomas,
- melanomas or
- renal cell carcinomas
have spread to the adrenal glands via the blood or lymphatic system. Metastases then form there.
In some cases, metastases are only found in one or both adrenal glands. In these cases, removal of the affected adrenal gland(s) as part of an adrenalectomy can help.
Various access routes and surgical procedures are available for an adrenalectomy.
In principle, a distinction is made between open and endoscopic surgical procedures. Endoscopic surgery has become increasingly popular in recent years. This procedure offers several advantages for the patient.
Endoscopic surgical procedure for an adrenalectomy
Benign tumors are generally removed in a minimally invasive manner nowadays. Two different access routes are used:
- the transperitoneal approach with the patient in the lateral position
- the retroperitoneoscopic approach with the patient in the prone position.
Whether one of the two approaches is superior to the other has not yet been clarified.
Open surgical procedure for an adrenalectomy
Nowadays, conventional surgical procedures are only used for
- extremely large tumors and
- malignant adrenal tumors
tumors.
The surgeon reaches the surgical site either by
- opening the abdominal cavity (laparotomy) or
- by opening the chest and abdomen together (thoraco-abdominal incision).
The access must be sufficiently large to allow safe access to the surgical site. A good overview of the surgical site is crucial when removing malignant tumors. Injury to the tumor always leads to the seeding of tumor cells. It is then virtually impossible to cure the patient.
The removal of an adrenal gland is a relatively safe procedure. Nevertheless, complications are possible with an adrenalectomy. In order to minimize the risk of complications, thorough preparation of the patient is essential.
Prevention of complications during an adrenalectomy
In the case of severe Cushing's syndrome, it may be advisable to suppress cortisol production. To this end, the patient is pretreated with appropriate medication. The electrolytes (blood salts) must also be well adjusted before the adrenalectomy.
Patients with Cushing's syndrome have a particularly high risk of thrombosis and infection. They must therefore undergo thrombosis prophylaxis and antibiotic prophylaxis.
Patients with Conn's syndrome should be pretreated with an aldosterone antagonist (e.g. Aldactone). This usually allows blood pressure to be controlled relatively well. Furthermore, the potassium deficiency must be compensated before the adrenalectomy.
Patients with a pheochromocytoma are particularly at risk from uncontrolled release of catecholamines during adrenalectomy. These hormones can be released during manipulation of the tumor. For this reason, the effect of catecholamines must be switched off.
There are drugs that block the corresponding receptors in the body. Patients must take the medication in the 10 to 14 days before the adrenalectomy. During this time, patients must also drink a lot. This is to compensate for the considerable lack of fluids caused by the pheochromocytoma.
Surgical complications of an adrenalectomy
Surgical complications are rare with an adrenalectomy. Bleeding can occur due to injuries to neighboring large blood vessels. These can also be dangerous.
Furthermore, neighboring organs can be injured, such as
What happens after an adrenalectomy depends on the reason for the removal of the adrenal gland.
Patients with Cushing's syndrome require cortisone after the procedure. Cortisone-producing adrenal tumors lead to the suppression of cortisol production in the healthy adrenal gland.
It can take months or even years for the function of the healthy adrenal gland to recover. During this time, cortisone must be substituted. Otherwise, a life-threatening cortisone deficiency (Addisonian crisis) can occur. If both adrenal glands have been removed, the patient must take cortisol for the rest of their life. The patient should also take a mineralocorticoid (fludrocortisone).
Patients with Conn's syndrome can usually do without some of their blood pressure medication after a successful adrenalectomy. The medication should be reduced slowly with close monitoring of the blood pressure values.
Chemotherapy with Mitotane may be necessary after the removal of an adrenal carcinoma. This question should be clarified in close consultation with an experienced endocrinologist.
The patient should also have regular follow-up visits after the adrenalectomy.
Various diseases can lead to the removal of the adrenal glands. Precise hormone diagnostics are a prerequisite for adrenalectomy. This enables doctors to recognize the various hormonal diseases.
The actual adrenalectomy is a comparatively uncomplicated operation. Nowadays, it is usually performed using minimally invasive techniques. The risks are also low if the patient is adequately prepared for the operation.
Adrenal carcinomas are rare tumors. They have a poor prognosis, which depends crucially on the quality of the operation. These tumors should therefore be performed in endocrine surgery centers.
