A colloid cyst is a pocket of connective tissue that contains a gel-like substance inside, called colloid, and may not cause symptoms or may lead to headache, drowsiness or hoarseness, for example, depending on where it developed.
The colloid cyst can appear in the brain or thyroid and be round or oval and varies in size, however, it does not tend to grow much or spread to other parts of the body.
Colloid cyst treatment is carried out by a neurologist or endocrinologist, and varies according to the type of cyst, and regular medical monitoring may be indicated to assess its growth or surgery to remove it.
Symptoms of colloid cyst
The main symptoms of colloid cyst are:
- Headache;
- Nausea or vomiting;
- Dizziness or drowsiness;
- Memory problems;
- Changes in mood and behavior;
- Difficulty walking;
- Urinary incontinence.
These symptoms may appear in the case of a colloid cyst in the brain, however, most of the time it is asymptomatic and is discovered in imaging tests to diagnose other diseases.
Likewise, a colloid cyst in the thyroid may have no symptoms, however, when it is large it can cause symptoms such as hoarseness, pain or the presence of a lump in the neck, or difficulty swallowing.
In the presence of symptoms of a colloid cyst, a neurologist or endocrinologist should be consulted so that tests can be carried out, the diagnosis confirmed and the most appropriate treatment initiated.
Don’t ignore your symptoms!
The diagnosis of a colloid cyst is made by a general practitioner, endocrinologist or neurologist through evaluation of symptoms, health history and imaging tests.
The main imaging tests that may be ordered by the doctor are magnetic resonance imaging or computed tomography, for example.
In addition, in the case of a thyroid colloid cyst, the doctor may also order an ultrasound or a biopsy of the cyst, called fine needle aspiration (FNA). See how thyroid FNA is performed.
Possible causes
The exact cause of colloid cyst is not completely known, but it is known to occur due to excessive growth of thyroid tissues.
In the case of a colloid cyst in the brain, it is believed that it may occur during the development of the central nervous system as the fetus develops during pregnancy.
Types of colloid cyst
The main types of colloid cyst are:
1. Colloid cyst in the thyroid
Thyroid colloid cyst is the most common type of benign thyroid nodule.
This type of cyst can cause increased production of hormones by the thyroid, being called an autonomous (hot) nodule, and can occasionally lead to hyperthyroidism. However, if the nodule is filled with fluid or blood, it is called a thyroid cyst.
Unlike the cyst, the nodule corresponds to a rounded and soft lesion that normally grows and may have a malignant appearance, which is one of the main concerns regarding the appearance of these lesions in the thyroid.
These nodules can be noticed when palpating the neck, and it is important to consult a doctor so that tests can be ordered and a diagnosis can be made. Find out more about thyroid nodule and how it is treated.
2. Colloid cyst in the brain
Colloid cysts in the brain can occur in the cerebral ventricles, which are regions responsible for the production and storage of cerebrospinal fluid (CSF).
Thus, the presence of the cyst can obstruct the passage of CSF and lead to the accumulation of fluid in this region, causing hydrocephalus, increased intracranial pressure and, in rarer cases, sudden death.
Although it is normally benign and asymptomatic, when diagnosed, it is important for the doctor to assess the size and position of the colloid cyst so that the possibility of obstruction of the CSF passage can be checked and treatment can be defined.
How the treatment is carried out
The treatment of a colloid cyst in the brain is carried out by a neurologist, and in the case of a colloid cyst in the thyroid, the treatment is carried out by an endocrinologist, and varies according to the size of the cyst or whether or not the person has symptoms.
In general, for colloid cysts that do not cause symptoms, the doctor may recommend periodic monitoring with imaging tests to check whether the cyst has grown.
However, in the case of a cerebral colloid cyst, if the person has hydrocephalus or other symptoms, the neurologist may recommend the placement of a ventricular drain to alleviate the drainage of cerebrospinal fluid, or surgery to remove the cyst. See how hydrocephalus is treated.
As for a thyroid cyst, the endocrinologist may recommend radiofrequency ablation surgery if the cyst is very large, or surgery to remove all or part of the thyroid. If there is uncontrolled production of hormones or if it is malignant, treatment with radioactive iodine may be performed in addition to surgery.
After surgery to remove the colloid cyst, the doctor usually sends part of the cyst to the laboratory so that it can be biopsied to confirm whether it is a benign cyst or whether it is malignant.
