Scarring from both skin grafts and skin cultures is severe. When healed, a person looks as if they had been badly burned. Occasionally thickened scars called keloids may appear. The site from which the skin graft is taken will also have mild scarring. Since wound size and blood loss are very large and dermabrasion leaves nevus cells behind which could potentially become cancerous, this treatment is only occasionally used now.
Dermabrasion also leaves severe scarring and the pigment usually seeps back.
Laser treatment and chemical peels have also been used to lighten nevi. These treatments burn away the extra pigment but leave the abnormal nevus cells behind which could also potentially turn cancerous. The pigment also often reappears. For these reasons, laser treatment and chemical peels are not usually used to treat large nevi of the body. They are occasionally used to treat facial nevi because improvement in cosmetic appearance is so important on the face.