Keloid Scars

What a keloid is

When skin heals, cells called fibroblasts lay down collagen to close the wound. Normally this slows down once the wound is closed, and the scar flattens and fades over 1 to 2 years. In a keloid, the fibroblasts stay overactive. They keep producing thick bands of collagen that push out past the original wound into healthy skin, forming a smooth, shiny, raised growth.

Keloids:

• Usually appear 3 months to a year after the injury, sometimes later
• Are firm or rubbery, pink, red, purple or darker than the surrounding skin
• Often itch, feel tender or cause burning or pulling sensations
• Can keep growing slowly for years
• Do not go away without treatment

Keloids are not cancer and do not turn into cancer.

Keloid vs hypertrophic scar

The main look-alike is a hypertrophic scar, which is thick and raised but behaves differently:

Causes and risk factors

Keloids follow skin injury, sometimes very minor:

• Ear and body piercings, the most common cause on earlobes
• Surgical incisions, especially chest surgery and cesarean sections
• Acne, especially on the chest, back and jaw
• Burns and cuts
• Vaccination sites, chickenpox scars, insect bites, tattoos
• "Spontaneous" keloids on the chest without remembered injury

Risk factors include:

• Darker skin: keloids are up to about 15 times more common in people with darker skin
• Age 10 to 30, with higher risk during puberty and pregnancy
• Family history: about a third or more of people with keloids have a relative with them
• Wound tension: areas where skin is stretched, such as the chest and shoulders
• Infection or slow healing of the original wound

Diagnosis

A dermatologist usually diagnoses a keloid by looking at it and asking about the injury. A biopsy is done only if the growth looks unusual, appeared without injury, grows fast, bleeds or ulcerates, to rule out conditions such as dermatofibrosarcoma protuberans, which can mimic a keloid.

Treatment

No single treatment works for everyone, and combinations work best. Results take months.

Steroid injections

Corticosteroid injections (usually triamcinolone) directly into the keloid every 4 to 6 weeks are the first-line treatment. They flatten and soften keloids and reduce itch and pain in most people. Side effects include thinning or lightening of the surrounding skin and small visible blood vessels.

Silicone and pressure

• Silicone gel or sheets, worn 12 to 24 hours a day for several months, help soften and flatten newer keloids and prevent recurrence.
• Pressure therapy: pressure earrings after earlobe keloid removal, or pressure garments for larger areas, worn most of the day for 6 to 12 months.

Cryotherapy

Freezing with liquid nitrogen, often combined with steroid injections, works best for small keloids. It can lighten darker skin.

Surgery

Cutting a keloid out alone leads to regrowth in most people, sometimes larger than before. Surgery is used with follow-up treatment: steroid injections at and after the operation, pressure, or radiation. Earlobe keloids respond particularly well to excision followed by injections and pressure earrings.

Radiation therapy

Low-dose radiation to the wound, started within a day or two of surgery, lowers recurrence rates considerably. It is usually reserved for adults with resistant keloids.

Other options

• 5-fluorouracil (5-FU) injections, often mixed with steroid
• Laser treatment (pulsed dye laser) to reduce redness and itch
• Intralesional cryotherapy for larger keloids
• Botulinum toxin and other emerging injections, under study

Over-the-counter scar creams such as onion extract have little evidence for keloids.

Prevention for keloid-prone people

• Avoid elective skin trauma: piercings, tattoos and cosmetic surgery, particularly on the chest, shoulders and ears.
• Treat acne early to prevent inflamed lesions that scar.
• Tell your surgeon you form keloids. They can use tension-free closure and plan steroid injections or silicone straight after surgery.
• Start silicone sheets or gel as soon as a wound has closed, and continue for at least 2 to 3 months.
• Keep new scars out of the sun to limit darkening.

Outlook

Keloids are benign, but they are a chronic condition that tends to recur. With combined treatment, most can be made flatter, softer and less symptomatic, though complete, permanent removal is not always possible. Early treatment of a young keloid works better than treating a large, old one.

Frequently asked questions

What causes keloids?

Keloids form when the skin's healing response does not switch off, so fibroblasts keep producing collagen after a wound has closed. Genetics, darker skin, age 10 to 30 and skin tension all increase the risk. Common triggers are piercings, surgery, acne and burns.

Can keloids be removed permanently?

Sometimes, but recurrence is common. Surgery alone has a high regrowth rate, so it is combined with steroid injections, pressure or radiation. With combined treatment, many earlobe keloids stay away, while chest and shoulder keloids are harder to cure.

Do keloids go away on their own?

Rarely. Unlike hypertrophic scars, which often flatten over 1 to 2 years, keloids usually persist or slowly grow. Some soften slightly with age, but most need treatment if they cause symptoms or concern.

How do I know if my piercing bump is a keloid?

A piercing bump that appears within days and is soft, red or weeping is usually irritation or a small infection. A keloid is a firm, smooth, rubbery lump that develops over months and grows larger than the piercing site. A dermatologist can confirm it.

Are keloids dangerous?

No. Keloids are benign and do not become cancer. They can itch, hurt and limit movement when over joints. A lump that appeared without injury, grows quickly or bleeds should be checked, because rarely another growth can look like a keloid.