Keloid

What a keloid is

When skin heals, cells called fibroblasts lay down collagen to close the wound. Normally, collagen production slows once the wound is closed and the scar flattens and fades over 12 to 18 months. In a keloid, fibroblasts stay overactive. Collagen keeps building up in thick, disorganized bundles, and the scar spreads out like a claw into the normal skin around it.

Keloids can appear weeks to months, or occasionally years, after the injury. Some appear after trauma so minor that the person does not remember it. These are sometimes called "spontaneous" keloids, typically on the chest.

Symptoms and appearance

• a firm or rubbery lump or plaque, raised above the skin
• extends beyond the original wound boundary
• pink, red or purple when new; often darker brown than the surrounding skin over time, especially in darker skin
• shiny surface without hair
• itching, tenderness, pain or a burning feeling
• shapes vary: round on earlobes, butterfly-shaped on the shoulders, dumbbell-shaped across the chest
• continues growing slowly over months or years

Keloids on joints can tighten the skin and limit movement.

Keloid vs hypertrophic scar

Causes and risk factors

Any skin injury can trigger a keloid in a prone person:

• ear and body piercings (the earlobe is one of the most common sites)
• surgical incisions, including cesarean sections and chest surgery
• acne, especially on the chest, back and jaw
• chickenpox, insect bites, vaccinations and scratches
• burns, tattoos and folliculitis

Factors that raise the risk:

• Skin color: keloids are much more common in people of African, Asian and Hispanic descent.
• Family history: keloids run in families, suggesting a genetic tendency.
• Age: most first appear between ages 10 and 30.
• Hormones: keloids may appear or grow during puberty and pregnancy.
• Location and tension: skin under constant stretch, such as the chest and shoulders, is more prone.

More on why keloids form and how to lower your risk is in keloid formation.

Diagnosis

A dermatologist usually diagnoses a keloid by looking at it and asking about past injuries. A skin biopsy is only needed when the lump appeared without injury, looks atypical, ulcerates or keeps growing quickly, to rule out other growths such as dermatofibroma or, rarely, dermatofibrosarcoma protuberans or skin cancer.

Keloid treatment

No single treatment works for everyone, and combinations work best. Treatment needs patience: many sessions over months.

Corticosteroid injections

Injections of triamcinolone directly into the keloid every 4 to 6 weeks are the first-line treatment. They flatten and soften the keloid and relieve itching. Side effects include thinning of nearby skin, lighter skin color and small visible blood vessels.

Surgery with follow-up treatment

Cutting out a keloid alone leads to recurrence in a large share of cases, and the new keloid may be bigger. Surgery is therefore combined with:

• steroid injections into the wound edges at and after surgery
• pressure therapy, such as pressure earrings worn for 12 hours or more a day for several months after earlobe surgery
• radiation therapy, given within a day or two of surgery, which substantially lowers recurrence for difficult keloids

Other treatments

• Silicone gel sheets or gel: worn daily for several months, they flatten and soften scars, especially early ones.
• Cryotherapy: freezing with liquid nitrogen, most effective on small keloids. It can lighten darker skin.
• 5-fluorouracil (5-FU) injections, often combined with steroids, for resistant keloids.
• Pulsed dye laser: reduces redness and itch.
• Botulinum toxin and other injections are being studied.

Relieving symptoms

Antihistamines, moisturizers and steroid tape can help with itch. Avoid scratching, which can enlarge the keloid.

Prevention for people prone to keloids

• Avoid elective procedures such as piercings and cosmetic surgery, especially on the chest, shoulders and earlobes.
• Treat acne early to prevent scarring.
• Tell your surgeon about previous keloids. Techniques that reduce skin tension, early silicone and preventive steroid injections help.
• Start silicone sheets or gel on new wounds once the skin has closed, and protect new scars from the sun.
• If a piercing site starts to thicken, remove the earring and see a dermatologist early.

Outlook

Keloids do not turn into cancer and do not spread elsewhere in the body. Without treatment, they usually persist and may slowly enlarge. With combined treatment, most keloids become flatter, softer and less itchy, but they often recur, so long-term follow-up is common.

Frequently asked questions

What does a keloid look like?

A keloid is a raised, firm, smooth and shiny scar that spreads beyond the edges of the original wound. It may be pink, red or purple at first and often becomes darker than the surrounding skin. Earlobe keloids are usually round lumps; chest keloids are often wide and claw-shaped.

Can a keloid go away on its own?

Rarely. Unlike hypertrophic scars, which often flatten over a year or two, keloids usually persist and may slowly grow. Some become softer and paler in older age. Treatment such as steroid injections is usually needed to flatten them.

Why do keloids come back after removal?

The surgery itself is a new wound, and the same overactive healing response that caused the original keloid can start again, often more strongly. That is why surgery is combined with steroid injections, pressure therapy or radiation, which greatly lower the chance of recurrence.

How do I get rid of a keloid on my ear piercing?

Earlobe keloids are usually treated by cutting them out and then preventing recurrence with steroid injections and pressure earrings worn for several months, or with radiation for repeat keloids. Small ones may respond to steroid injections or cryotherapy alone. Avoid re-piercing the same area.

Are keloids cancerous?

No. Keloids are benign overgrowths of scar tissue and do not become cancer. A lump that appears without injury, grows rapidly, bleeds or ulcerates should still be checked, because a few rare skin tumors can look similar and a biopsy can tell them apart.