What Are Keloid Scars?

Darker skin is more vulnerable

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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.

Raised scars are visible on a woman's shoulder.

piccerella / Getty Images

Risk Factors

Although a keloid scar can form on anyone, some ethnic groups are at a greater risk of developing them. People with darker 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.

Some areas of the body do seem more susceptible to keloid scars, including the deltoid region of the upper arm, the upper back, and the sternum. The earlobes and the back of the neck are also common sites.

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.

Skin or muscle tension seems to contribute to keloid formation, as is evidenced by the most common sites of their formation (the upper arm and back). But if that was the full story, you would expect that other sites, such as the palm of the hand or the soles of the feet, to be just as vulnerable. However, that's not the case.

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

Other theories for the causes of keloid scarring include:

  • Deficiency or excess in melanocyte-stimulating hormone (MSH)
  • Decreased percentages of mature collagen and increased soluble collagen
  • Blockage of very small blood vessels and the resulting lack of oxygen

Work is being done to identify the cause(s) of keloids, and it's likely to lead to better preventative medicine and more effective treatments in the future.

Prevention

The fact is that there may be little you can do if you are unfortunate enough to have the sort of skin that reacts by forming keloid scarring. You can assist the healing process by keeping any wounds clean.

If you know you are susceptible because of previous experience or a family connection, then you can avoid taking extra risks. Do not get piercings or tattoos, and make sure you tell your healthcare provider about your susceptibility if you're going to have surgery.

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

It's common for keloids to come back after removal. The rate of recurrence is up to 50%.

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%. Lasers have 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, injections of a steroid such as triamcinolone can be injected into the lesion to keep recurrence at bay. The injections are given every four to six weeks as needed.

Non-Surgical Treatments

Interferon therapy (drugs 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 can theoretically 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 at the time of the surgery and the second injection about a month later.

However, this type of treatment is variously reported as having between a 50% to 70% rate of recurrence.

Another option combines surgery with external type radiotherapy. Radiation has the effect of interfering with skin growth (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 the most effective treatment. It may be worth getting a second opinion before proceeding with either treatment.

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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6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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