Adrenal cysts in adults and children

A capsule-bound cavity in the adrenal endocrine glands – an adrenal cyst – is a rare pathology and is often unexpectedly discovered during visualization (during ultrasound or computed tomography). This gave grounds to classify cysts of this localization as incidentalomas, that is, accidentally detected tumor-like formations. According to ICD-10, the code is E27.8 (other disorders of the adrenal glands). [ 1 ]

Epidemiology

When examining the abdominal and peritoneal organs using computed tomography or magnetic resonance imaging, 4-5% of patients are found to have incidental findings in the form of various adrenal masses, called incidentalomas by specialists. Most often, these are adenomas (more than 67%) and cystic lesions (9.7%). Endothelial or lymphangiomatous cysts account for almost 45% of these lesions and are usually small, from 0.1 to 1.5 cm in diameter. Adrenal pseudocysts without epithelial lining are the next most common type (39%) and most likely represent encapsulated remnants of previous adrenal hemorrhages.

However, according to clinical surgery data, among pathologies of this localization, cysts account for 0.68% of cases.

According to statistics, the most common adrenal cysts are endothelial (from 2 to 24% of cases), and the rarest is parasitic echinococcal (0.5%).

Most often, the formation is one-sided, that is, a cyst of the right adrenal gland or the left.

Moreover, adrenal cysts are found in men three times less often than in women. [ 2 ], [ 3 ]

Causes adrenal cysts

As in many cases of abdominal cystic lesions, specialists often fail to establish the causes of adrenal cysts. However, among the versions of their origin, first of all, are congenital anomalies of embryogenesis of the tissues of the cortex and medulla of the adrenal glands and injuries to the abdominal region affecting them. [ 4 ]

Adrenal cysts are divided into:

• epithelial or true cyst, which has a clearly distinguishable membrane lined with epithelium;
• endothelial or vascular cysts - lymphangiomatous (lymphangiectatic) and hemangiomatous (angiomatous);
• pseudocyst or hemorrhagic cyst, which occurs either as a result of a hematoma or is formed in adrenal tumors (benign or malignant) - as part of them.

A parasitic cyst of the adrenal gland is also distinguished - when the gland is affected by echinococcus larvae (Echinococcus granulosus). [ 5 ]

In children, adrenal cysts are not only vascular, [ 6 ] but can also be pseudocysts: with a tumor in the adrenal medulla - pheochromocytoma, cystic neuroblastoma or teratoma. [ 7 ]

An adrenal cyst in a newborn is a congenital anomaly and can also be the result of birth trauma – perinatal hemorrhage, that is, bleeding into the adrenal glands. [ 8 ]

In addition, hemorrhage into the adrenal glands in adults is possible with shock, trauma, meningococcal septicemia, and disseminated intravascular coagulation (DIC) syndrome.

Risk factors

Likewise, specific risk factors for the development of adrenal cysts have not been determined, although, according to foreign studies, some conditions and diseases have been identified in which these formations are often found.

Thus, adrenal cysts are detected in patients with refractory arterial hypertension, polycystic kidney disease and kidney cancer, abdominal aortic aneurysm, pancreatic cyst (then a cyst of the left adrenal gland is detected), with congenital Klippel-Trenaunay syndrome and some other genetically determined anomalies, such as cerebroretinal angiomatosis.

It is extremely rare for an adrenal cyst in women to be accidentally detected during an ultrasound examination during pregnancy or as a metastasis of a malignant breast tumor.

Pathogenesis

It is believed that the pathogenesis of vascular lymphangiomatous cysts is associated with ectatic changes (expansion) of lymphatic vessels in the adrenal medulla or cystic degeneration of an existing nodular benign formation - mesenchymal hamartoma. And pathological changes or abnormalities of small blood vessels of the adrenal gland, including aneurysms and hemorrhage of the adrenal veins, lead to the formation of angiomatous cysts.

An epithelial cyst develops from cells of the embryonic tissue – mesenchyme and is a consequence of intrauterine developmental disorders.

The mechanism of formation of adrenal cysts with foci of primary neoplasms of these glands (adenomas of the adrenal cortex, carcinomas or pheochromocytomas) is unclear.

Symptoms adrenal cysts

As experts note, an accidentally discovered adrenal cyst rarely causes symptoms: most of these formations, especially epithelial cysts, are asymptomatic (and do not require treatment).

The first signs in the form of pain in the abdomen or side and gastrointestinal disorders appear when the cyst is large: it can be detected by palpation. And a lymphangiomatous cyst can be of such a size that it can partially or completely replace the adrenal gland. [ 9 ]

A palpable abdominal mass, anemia, and jaundice are seen with adrenal cysts in infants.

Symptoms of an echinococcal cyst include general malaise and weakness, loss of appetite, increased body temperature, and constant dull pain in the hypochondrium.

Complications and consequences

The main complications and consequences of cystic formations in the adrenal glands are: compression of surrounding vessels and tissues, infection and development of inflammation, bleeding, rupture of the cyst with hemorrhage and shock. [ 10 ]

Diagnostics adrenal cysts

In addition to examination and anamnesis, diagnostics of adrenal endocrine gland cysts requires laboratory tests. The following are required: clinical and biochemical blood tests; to exclude hormonally active (functional) formations, blood tests are taken for the serum level of adrenal hormones (cortisol, ACTH, aldosterone, renin); general and daily urine tests - for metanephrine and catecholamine metabolites. Blood tests for eosinophils and antibodies to Echinococcus granulosus are also required.

Instrumental diagnostics include ultrasound, CT and MRI.

An adrenal cyst on an ultrasound of the abdominal cavity appears as a homogeneous hypoechoic structure with smooth contours. However, in adults, the adrenal glands are often poorly visualized on ultrasound.

An adrenal cyst is more clearly visible on CT, and this method makes it possible to determine the density of the formation, the thickness of the capsule walls, internal partitions, contents, calcification (detected in 15-30% of cysts), and the condition of the surrounding tissues. For the purpose of differentiation, computed tomography with contrast and MRI are performed.

Differential diagnosis

Differential diagnosis should take into account the possibility of hyperplasia and adenoma of the adrenal cortex, pheochromocytoma with cystic changes, adrenocortical carcinoma, myelolipoma, etc.

Treatment adrenal cysts

In case of a large cyst (more than 4-5 cm in size), as well as in the presence of symptoms, surgical treatment is performed. This is resection or laparoscopic removal of the adrenal cyst. See – Removal of the cyst [ 11 ]

In addition, decompression of the cyst is performed by percutaneous fine-needle aspiration of its contents (with subsequent examination). However, there is a high probability of repeated accumulation of fluid in the cystic cavity. [ 12 ]

Laparoscopic removal of the cyst membrane (decortication), marsupialization, and puncture sclerotherapy of the cavity with ethanol can be performed. [ 13 ]

In cases of pseudocysts with foci of primary adrenal cortex adenoma or carcinoma, laparoscopic adrenalectomy is used.

Small asymptomatic cystic lesions should be monitored regularly with ultrasound or CT scans and adrenal hormone levels. [ 14 ]

After removal of the parasitic cyst, medications from the antihelminthic group are prescribed: Medizol (Albendazole) or Vermox (Mebendazole).

Read also:

• Treatment of cysts
• Folk treatment of cysts

Prevention

There are no special preventive measures for adrenal cysts.

Forecast

For the vast majority of incidentally diagnosed benign adrenal cysts, the prognosis is good.