Although they can look similar, hypertrophic scars and keloids are not the same. A hypertrophic scar stays within the boundaries of the incision; a keloid extends beyond the incision line itself. With hypertrophic scars, more collagen forms than is broken down. Keloid scars are caused by uncontrolled production of collagen. Some people are highly susceptible to keloid formation and form keloids with even minor scratches. Steroid injections can control itching in hypertrophic scars. Silicone gel sheeting and over the counter scar ointments can be effective, but must be used on the wound for at least 12 hours a day. Keloids once formed are difficult to treat non surgically. Removing the keloid in combination with steroid injections, radiotherapy or laser treatments, can decrease the recurrence of keloids.