Minimally Invasive Technologies for Treatment of HTS and Keloids: Low-Dose 5-Fluorouracil

Both hypertrophic scar (HTS) and keloid are pathological scars that tend to overgrow and overproduce extracellular matrices, lead to large-sized scars along with severe pain and itching, and even result in functional disability. In particular, keloids are considered as benign skin tumors due to their nature of uncontrolled growth beyond the original wound boundary and invasion into normal skin; therefore, anticancer therapy has been employed in keloid therapy. 5-Fluorouraci (5-FU), a pyrimidine analog, is a commonly used chemotherapy agent and it has also been previously used in keloid treatment with intralesional injection at a concentration of 40–50 mg/ml. The authors propose the use of low dose 5-FU at the concentration of 1.5–5 mg/ml for establishing a sustainable chemotherapy without causing significant side effects in order to cure keloid by a possible long-term chemotherapy, which is essential for controlling keloid relapse. Since 2002, the authors have treated over 10,000 cases of keloids and demonstrated that this approach is effective and safe. In addition to intralesional injection treatment of keloids and HTS with combined use of 5-FU and steroids, it was also used for preventing keloid recurrence after surgical excision. In this chapter, the authors introduce the general background of keloid and HTS chemotherapy, the rational of using low-dose drugs, and the clinical protocol of low-dose 5-FU injection therapy and its applications along with typical case presentation.