True about keloid:

Ref. Sabiston Textbook of Surgery. Pg. 142   Keloid  is the type of abnormal scar formation  and it is most commonly confused with hypertrophic scar . Keloid scars resemble hypertrophic scars superficially in that they are elevated boundary of the original injury or incision . Males and females equally prone to keloid scars ,but dark skin types ,especially african genetic origin are 15 times more prone . Keloid has familial tendency and it spreads beyond wound site Similarity between keloid and hypertrophic scar is both involves abnormal collagen metabolism resulting in a higher than usual proportion of type 3 collagen and both associated with tissue hypoxia and sustained levels of TGF BETA 1 . Keloid contain thick collagen and have increased levels of epidermal hyaluronic acid, whereas hypertrophic scars have more nodular microscopic structure with fine collagen bundles and increased conc of alpha actin . Treatment -intralesional steriods injections .