Scarring, postoperative skin discoloration or keloid formation are potential complications. Keloid scars can develop after surgery. Low-dose, superficial radiotherapy is sometimes used to prevent recurrence of severe keloid and hypertrophic scarring. Keloid scars have decreased decorin expression compared to healthy skin. Treatment of a keloid scar is age dependent. Indications for keloid and hypertrophic scar were added in the 1980s. Prolonged cases of AKN can cause keloid formation due to chronic irritation from folliculitis. If left untreated over time, this can cause keloid scarring in the beard area. However, clobetasol propionate can be used as an alternative treatment for keloid scars. In some people, keloid scars form spontaneously. Lone excision of keloid scars, however, shows a recurrence rate close to 45%. A special form is the keloid, which derives from hyperplastic growth of scars. Keloid scars can occur on anyone, but they are most common in dark-skinned people. Tea tree oil, salt or other topical oil has no effect on keloid lesions. If the keloid becomes infected, it may ulcerate.