Not uncommonly patients come in complaining that they are prone to keloids.  They may have gotten a cut or a burn that resulted in a scar.  Upon examination,  however, I see no keloid–just a regular scar.  What is the difference?  When we develop a wound, our body sends out signals that cause new skin cells to migrate to the wounded area to repair the problem.  If the injury involves the layer of the skin called the dermis, it will result in some type of scar– even if we can’t really see it.  Not all scars, however, are keloids.

There are signals that tell the body to repair an injury.  There are also signals that tell the body that the wound is healed and that it can stop building new tissue.  A keloid is a type of abnormal scarring process in which the signals which would cause the skin to stop growing after an injury, such as a cut, don’t get switched off properly and the skin continues to grow despite the wound having healed.  The result is a scar that is much larger than, and outside the boundaries of, the injury. Below is an example of a keloid formed from a tiny earring hole:

What’s the difference between a hypertrophic scar and a keloid?  Most scars flatten out over time, however, some scars, particularly in areas of tension, such as the chest, may thicken.  Hypertrophic scars are thicker than normal but unlike a keloid they stay within the boundaries of the injury:

Keloids and hypertrophic scars are harmless but many people find them unsightly and sometimes they are itchy and painful.  Treatment may include injected or topical steroids, surgery, pressure earrings, imiquimod, scar gels and massage.  Steroids may be necessary for itchy or inflamed keloids and scars.