A dermoid cyst is a sac of cells containing tissues that are usually present on the skin’s surface. They form during fetal development and grow slowly, so a person may not notice them until late childhood or adulthood.

Dermoid cysts are usually noncancerous, or benign.

While doctors do not know exactly why they occur, all dermoid cysts are congenital, meaning a person has them from birth. The cysts may continue to grow slowly, and people need surgery to remove them.

This article explains dermoid cysts in more detail, how doctors treat them, and more.

A newborn with a dermoid cyst.Share on Pinterest
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A dermoid cyst is a small sac of cells that is present from birth. It is a type of benign tumor.

Skin cells grow inside the cyst, complete with hair follicles and glands that secrete sweat and oil.

The skin cells inside the cyst grow and multiply just like external ones, but the dead cells and old secretions build up inside. Over time, the cyst grows and can encroach into nearby bones, nerves, or organs.

People usually discover most dermoid cysts during childhood before the age of 5 years, but they can remain unnoticed until adulthood.

Dermoid cysts usually grow in the head, face, and neck region, but they can form anywhere in the body. They appear as dome-shaped lumps just under the skin.

Most dermoid cysts occur in the periorbital region, the area around the eye socket. Many people get them along the outer edge of one eyebrow.

More rarely, dermoid cysts can grow in the nasal cavities and sinuses. A 2020 study estimates that around 11% of dermoid cysts in the head and neck area will be in the nasal region.

Dermoid cysts can also grow on a person’s ovaries. A 2016 study explains that, although ovarian dermoid cysts are present from birth, doctors may not discover them until the person is 20–40 years old.

Rarely, dermoid cysts can grow or extend into a person’s brain or spine.

The symptoms depend on where the cyst is.

Most dermoid cysts grow slowly and appear as a lump underneath the skin. However, if they push against a bone, they can make it grow irregularly.

Periorbital dermoid cysts may appear as a painless bump on the eyebrow. The eye area may inflame and swell if the cysts burst or become infected.

People with dermoid cysts in the nasal area may experience swelling and a blocked or runny nose.

Most people with ovarian cysts do not experience any symptoms. However, some people may have pain or discomfort in one side of the lower belly area.

Symptoms of cysts in the brain or spine vary depending on their precise location. Some people experience:

Dermoid cysts occur while a fetus is developing.

While the fetus is in the embryonic stage, skin cells and structures get trapped in the wrong place and form a cyst.

However, doctors and researchers do not fully understand why this happens.

Doctors can often diagnose dermoid cysts with a physical exam. Periorbital dermoid cysts tend to look and feel similar and are usually on the outer third of the eyebrow.

If doctors are concerned about the cyst growing into nerves, blood vessels, or a person’s eye, they may recommend imaging tests, such as a CT or MRI scan. These tests also help doctors diagnose people with cysts that are deeper in the body, such as the spine or brain.

For ovarian cysts, doctors usually perform a pelvic exam or use a transvaginal ultrasound. For this test, doctors insert the ultrasound wand into the person’s vagina to look for any abnormal growths.

Around 85% of dermoid cysts are in the head and neck region, near the surface of the skin. These types are relatively easy to remove.

Untreated cysts may rupture, or burst, and there is a risk of them becoming infected.

If the cysts grow or extend into the brain or spine, they may press against nerves or blood vessels, disrupting their function. Infected cysts in the brain or spine can cause abscesses, meningitis, and bone marrow inflammation.

According to a 2016 study, ovarian dermoid cysts can cause ovarian torsion, wherein the ovaries twist over themselves. This can interfere with the organ’s blood supply.

There is also a possibility of ovarian dermoid cysts causing peritonitis or bowel obstruction.

Doctors usually perform surgery to remove dermoid cysts, and the outlook is generally good. These cysts do not usually grow back again.

Most dermoid cysts grow in the periorbital area, and doctors can usually remove them under local anesthetic, either in their offices or as an outpatient procedure. The person will be awake during this time.

Surgeries for other dermoid cysts depend on their location and size, but they usually involve a hospital stay. These include:

  • Craniotomy: During this procedure, surgeons drill a hole in the skull to remove a cyst from the brain. People having this surgery need a general anesthetic and will be unconscious during the operation.
  • Ovarian cystectomy: This is when surgeons remove the cyst from one or both ovaries. According to the American College of Obstetricians and Gynecologists, doctors may also conduct a laparoscopy. During a laparoscopy, doctors make a small cut in the person’s lower abdomen and insert a thin camera.
  • Oophorectomy: Surgeons may remove the whole ovary, called an oophorectomy. Doctors usually do this if the ovary has twisted or if the cyst is particularly large.
  • Microsurgery: In this procedure, surgeons rely on microscopes to guide them. This is particularly relevant when doctors remove cysts from a person’s spine.

Dermoid cysts begin while a fetus is developing inside the uterus. No one can prevent this.

Researchers describe them as developmental anomalies, but doctors do not know why they occur.

Most people recover completely after surgeons remove the dermoid cysts. They try to remove the entire cyst without bursting its walls, to minimize the risk of infection.

Once a surgeon completely removes them, dermoid cysts do not grow back.

If the cysts are tangled with, or stuck to, other parts of the person’s body, surgeons may not be able to remove them quite so neatly. There is a slim chance that these cysts will recur.

Dermoid cysts are benign and slow growing, but the smaller they are, the easier it is to remove them completely.

Anyone who has a lump for 2 weeks or more should contact a doctor.

If a person with a cyst notices that the surrounding area is painful or interferes with their usual activity, they should talk with a doctor as soon as possible.

A person should seek immediate medical help if the cyst changes color or bursts.

This section answers some common questions about dermoid cysts.

Is a dermoid cyst cancerous?

The majority of dermoid cysts are benign, meaning noncancerous.

However, a few case studies say they may become cancerous.

Can dermoid cysts return?

If doctors can remove the cyst without damaging its cell wall, they are unlikely to return.

Some cysts, however, grow into nearby organs, and doctors may not be able to remove the whole cyst. In these cases, there is a small chance that the cyst will continue to grow.

Can dermoid cysts go away on their own?

Dermoid cysts do not go away on their own. They grow slowly and can be present for many years before a person is aware of them.

However, there is a possibility that the cyst can burst or become infected. It may also push against nerves or blood vessels as it grows.

Doctors recommend surgery to remove the cyst before these issues occur.

Dermoid cysts are benign growths that occur when a fetus is developing. Skin cells form inside the cyst, and they may contain sweat and oil glands, and hair follicles.

Over time, these cysts grow, and doctors recommend surgery to remove them.

Dermoid cysts are present from birth but may not be noticeable until a child is about 5 years old. Most dermoid cysts are present around the eye area, but they can occur anywhere in the body.