keloid

A keloid is a type of raised scar that grows beyond the boundaries of a skin injury and does not spontaneously regress. Unlike hypertrophic scars, keloids extend beyond the original wound and tend to persist.

Keloids most commonly develop after skin trauma such as surgical incisions, piercing, burns, acne, or minor wounds. They are more frequent in people with darker skin tones and may run in families. Common sites include earlobes, shoulders, chest, and upper back.

Keloids formation reflects abnormal wound healing with excessive collagen deposition, especially type III collagen, persistent fibroblast activity, and overexpression of transforming growth factor-beta and other cytokines.

They are firm, rubbery, and can be shiny, sometimes itchy or painful. Diagnosis is usually clinical; a biopsy is rarely needed unless cancer is suspected or diagnosis is unclear.

Treatment is individualized; many keloids do not require treatment. Options include intralesional corticosteroids (e.g., triamcinolone) as first-line, silicone gel sheets or pressure therapy, cryotherapy for small lesions, laser therapy (pulsed-dye or CO2) to flatten, and surgical excision with adjuvant therapies due to high recurrence rates; radiotherapy or 5-fluorouracil injections may be used in some cases.

Prevention focuses on minimizing skin injury, prompt treatment of wounds, and sun protection; recurrence risk remains even after therapy, particularly in high-risk populations.