What are adrenal tumors
The adrenal glands are located along the spine and large blood vessels near the top of the kidneys and are part of the endocrine system. Divided between medulla and cortex, they are responsible for producing substances that act in the control of the circulatory system (catecholamines) and hormones that act both in metabolism processes (cortisol, for example) and in sexual function (androgens).
When cells in the medulla or cortex proliferate uncontrollably, adrenal tumors occur. This growth is due to genetic mutations not corrected by the organism.
Because they are very rare, the risk factors for adrenal tumors have not yet been determined.
The presence of some genetic syndromes seems to predispose to the appearance of tumors, both malignant and benign, namely:
- Multiple endocrine neoplasia type 2 (MEN2);
- Neurofibromatosis type 1 (Von Recklinghausen’s disease);
- Beckwith-Wiedemann syndrome;
- Li-Fraumeni Syndrome;
- Paraganglioma syndrome (extra-adrenal pheochromocytoma); and
- Von Hippel-Lindau Syndrome.
Adrenal tumors are not always malignant: the occurrence of benign tumors is more frequent. Next, we will discuss the two types of malignant adrenal tumors.
Types of adrenal tumors
When malignant, adrenal tumors can be of two types: adrenal (or adrenocortical) carcinoma and pheochromocytoma.
Adrenal or adrenocortical carcinoma is a tumor that originates in the cortex of the adrenal itself. In most cases it is non-functioning, but it may be hyper-functioning in a small portion of the cases.
It is an uncommon tumor, with an annual incidence of 1 to 2 cases per 1 million people. It affects men and women equally and has three peaks of occurrence:
- Children aged 1 and 2 years;
- Children between 7 and 16 years old;
- Adults 50 years and older (most common).
In most cases (50 to 70%), the disease affects the left adrenal gland, and in 5 to 7% of cases it is bilateral.
Pheochromocytoma is a tumor that originates in the medulla of the adrenal gland and is extremely rare. Its most frequent sites of dissemination are lymph nodes, lung, liver and bones.
There is a type of pheochromocytoma, known as paraganglioma, whose differential characteristic consists in being ectopic or extra-adrenal, arising from the para-aortic sympathetic ganglia.
Even rarer than adrenal carcinoma, pheochromocytoma has a very low incidence, being known to occur in 0.05 to 0.1% of hypertensive patients. Its peak incidence is from 30 to 40 years of age, but it can occur in younger people when associated with hereditary syndromes – in these cases, it tends to be more aggressive and have a greater probability of metastasis. It is usually bilateral.
Symptoms and signs of adrenal tumors
Benign adrenal tumors are usually asymptomatic, as are malignant ones in early stages. The malignant tumors in more advanced stages usually have symptoms similar to those of other types of cancer, such as:
- Weight loss for no apparent reason;
- Abdominal mass;
- Bleeding in the urine;
- Abdominal pain.
Symptoms directly related to adrenal carcinoma are alterations in the menstrual cycle, appearance of acnes and skin fragility, while the typical signs of pheochromocytoma are those linked to the release of catecholamines and adrenaline and noradrenaline metabolites, namely: hypertension, arrhythmia and/or hyperglycemia.
In children, the most common symptoms are caused by male hormones that the tumor can produce: excessive growth of facial and body hair, enlargement of the penis and breasts in boys and the clitoris in girls.
Diagnosis of adrenal tumors
Upon noticing the symptoms and seeking the help of a doctor, the patient will need to perform some tests to confirm the adrenal tumor diagnosis.
Blood and urine tests are usually prescribed to analyze hormone levels, in addition to imaging tests of the abdomen. Ultrasonography can identify changes in the size of the adrenals, and more specific tests, such as tomography, magnetic resonance and PET scans, can aid the study of lesions.
Adrenal carcinoma is usually diagnosed when the tumor reaches a volume greater than 6 cm. MRI is the most accurate method to assess it.
For pheochromocytoma, the evaluation tends to occur through laboratory measurements (blood and urine) of possible metabolites of adrenaline, noradrenaline and catecholamine (although about 15 to 20% of patients have normal levels of catecholamine). Elevated levels are usually diagnostic of the disease.
Typically, adrenal tumors are diagnosed early when CT scans are done for a different health-related issue – that is, detection is accidental. The specific diagnosis is usually at a more advanced stage, with the onset of symptoms, when tumors begin to press on other organs.
Treatment of adrenal tumors depends on their location, size, and the patient’s clinical condition. Initially, surgery to remove one or both adrenal glands is common – the procedure is called adrenalectomy. It is a procedure that can be minimally invasive, by robotic surgery and videolaparoscopy, or open route.
Radiotherapy, chemotherapy, and the use of other medications can complement the treatment of adrenal tumors after surgery. When surgery is not possible, systemic chemotherapy can be used.
Despite having a wide range of diagnostic tests, there is no prevention routine for adrenal tumors. With the onset of symptoms, a urologist or oncologist should be consulted.