What Are Keloid Scars?

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Keloid scars are defined as abnormal scars that are hard, smooth, and grow beyond the boundary of the original skin injury. The scar is a raised and ill-defined growth in the area of damaged skin, and it can cause pain, itching, and burning.

This article covers why keloid scars form and who is more likely to develop them. It also discusses several ways this type of scar can be treated, along with what you may be able to do to prevent them.

Raised scars are visible on a woman's shoulder.

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Risk Factors

Although a keloid scar can form on anyone, some ethnic groups are at a greater risk. People with more melanin in their skin, such as Black people, Asians, and Hispanics, are more susceptible.

Keloid scars are seen 15 times more frequently in highly pigmented ethnic groups than in White people. The scars are very rarely seen in people with albinism.

Some areas of the body are more prone to keloid scars, particularly parts where there is skin or muscle tension. This includes the deltoid region of the shoulder`, the upper back, and the sternum (breastbone).

The earlobes and the back of the neck are also common sites. Very rarely do keloids form on the eyelids, genitals, palms, or soles of the feet.

Causes 

It is not fully understood why or how keloid scars form. Skin trauma appears to be the most common cause, although scars can also form for no apparent reason.

Infection at a wound site, repeated trauma to the same area, or a foreign body in a wound can also be factors. There does appear to be a genetic factor to keloid scarring as well. If someone in your family has keloids, then you are at increased risk.

Another theory for why keloids form involves collagen—the major protein in your skin that keeps it strong and supple. Collagen plays a vital role in wound healing and scar formation. It's thought that an imbalance of collagen production can affect the wound healing process and contribute to keloid scars.

Work is being done to identify the exact causes of keloids. Knowing precisely what causes them will likely lead to better preventive medicine and more effective treatments in the future.

Prevention

Unfortunately, there is not much you can do to prevent keloid scars if your skin is prone to them. You can, however, assist the healing process by keeping any wounds clean.

If you know you are prone to keloid scars due to previous experience or a family history of them, then you can take extra precautions to avoid wounds. Do not get piercings or tattoos. If you are going to have surgery, let your healthcare provider know that you are more susceptible to keloid scarring.

Some healthcare providers say that all highly pigmented people should avoid tattoos and piercings, just to be on the safe side.

Treatment 

Keloid scars can be removed with surgical treatments, non-surgical treatments, and combinations of the two.

Surgical Treatment

Surgical removal of keloid scars has a very high regrowth rate, anywhere from 50% to 100%. Laser therapy has been tried as an alternative to knife surgery but so far the outcomes are no better.

After scar excision, a silicon gel or sheeting should be applied immediately to the excision site and used daily for six to nine months. The gel is clear and makeup can be applied over it.

If the keloid seems to be reappearing after surgery, a steroid such as triamcinolone can be injected into the lesion to keep the keloid from growing back. The injections are given every four to six weeks as needed.

Non-Surgical Treatments

Interferon therapy (medication acting on the immune system) has been reported as effective in reducing keloid scarring. However, it can have some significant side effects, including:

Prolonged compression of scar tissue may help soften and break up keloid scars, but the practicality of this option depends on the location of the keloid.

Other non-surgical interventions that are currently being tried with varying results include:

Combined Treatments

Because surgery alone is not very effective, healthcare providers can remove the scar and then provide steroid injections. One injection is given at the time of the surgery and a second injection is given about a month later.

However, scars are reported to recur after this type of treatment in about 50% to 70% of cases.

Another option combines surgery with radiotherapy. Radiation interferes with skin growth (specifically cells called fibroblasts) and collagen production. Research varies on which type of combination therapy is more effective.

Both radiotherapy and steroid drugs have side effects, so you need to discuss with your healthcare provider which treatment will be best for you. It may be worth getting a second opinion before proceeding with either treatment.

Summary

It is not entirely known why keloid scars form, but it is clear that people with darker skin and people with a family history of keloids are more likely to get them. If you are prone to keloids, the only way to prevent them is to avoid wounds as best as you can. While keloids can be treated with surgical removal or steroid injections, they are fairly likely to grow back.

A Word From Verywell

Keloids usually don't require treatment, but speak up if yours cause a problem for you, whether it's discomfort or embarrassment. Your healthcare provider can then work with you on what the best approach might be for getting rid of or at least minimizing your scar.

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9 Sources
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