Pilar cysts are flesh-colored bumps that can develop on the surface of the skin. They’re sometimes called trichilemmal cysts or wens. These are benign cysts, meaning they typically aren’t cancerous. Although pilar cysts aren’t necessarily a cause for concern, you may find them uncomfortable.

You may be able to identify some of the characteristics of pilar cysts on your own, but you should still see your doctor for an official diagnosis. They can make sure the bump isn’t another type of cyst. They’ll also advise you on your next steps.

Keep reading to learn more about how these cysts present, whether they should be removed, and more.

Pilar cysts grow within the surface of your skin. Although 90 percent of pilar cysts occur on the scalp, they can develop anywhere on the body. Other possible sites include the face and neck. Most people end up having more than one pilar cyst at any given time.

These types of cysts can range in size. Some can be the size of a quarter, and others can grow to the size of a small ball. This process happens gradually over a long period of time.

Pilar cysts are the same color as your skin. They’re also round in shape, sometimes creating a dome-like bump on the surface of your skin. The cysts are usually firm to the touch but smooth in texture. Pilar cysts don’t contain pus, and they shouldn’t be painful to the touch.

These cysts usually develop without causing any problems. However, it’s possible that a cyst may rupture on its own or as a result of trauma. If this happens, you may notice a rash, pain, or irritation in the affected area.

Although it’s not common, infection is possible. This can lead to pain and oozing at the cyst site. You may be more vulnerable to infection after a cyst has ruptured, or after an incision is made in an attempt to remove it.

Pilar cysts gradually develop in the epithelial lining of your hair follicles. This lining contains keratin, which is a type of protein that helps create skin, hair, and nail cells.

Over time, the protein continues to build up in the hair follicle and creates the bump that’s characteristic of a pilar cyst.

Pilar cysts may be hereditary. They’re also more common in middle-aged women.

If your cyst has ruptured, you may also be at an increased risk for irritation and swelling at the site of the cysts.

Although you may be able to self-diagnose a pilar cyst based on the signs and your individual risk factors, it’s still important to see your doctor for confirmation. They can rule out other underlying causes that may be more serious.

To make a diagnosis, your doctor will perform a biopsy. This involves taking a small sample of tissue in the area and sending it to a lab for microscopic evaluation. A CT scan is sometimes used to rule out cancer and other types of cysts.

These diagnostic tools can also look at the underlying layers of the cysts to help see if any more are forming.

Treatment isn’t medically necessary for pilar cysts. However, many people consider removal options for cosmetic reasons or due to general discomfort caused by the cysts.

In some cases, your doctor may recommend draining the cyst with a small cut at the site of the bump.

However, surgical removal is the most effective treatment method. In this approach, your doctor will remove both the cyst and the epithelial lining from the underlying hair follicle. This stops the cyst from producing more keratin that can lead to recurring bumps.

After surgery, there may be a small scar left where the cyst originally was. Despite removal, it’s possible for these types of cysts to eventually return.

Any type of surgery or incision puts you at risk for infection and possible scarring. If you experience redness, irritation, or pus drainage from the area, see your doctor. They can prescribe oral antibiotics to treat these symptoms.

You should also see your doctor if you experience any pain after the surgery.

Pilar cysts are usually harmless, so surgical removal is up you and your doctor’s discretion.

Even if you don’t find a pilar cyst bothersome, it’s important to keep an eye on it. See your doctor if you notice any changes outside of the gradual growth and development expected of a pilar cyst.

In rare cases, pilar cysts can become cancerous. When this happens, the cysts tend to grow quickly and multiply. Surgery is required to remove any cancerous tumors.