Unwanted hair growth induced by topical epidermal growth factor during wound healing: true or myth?

Dear Editors, Epidermal growth factor (EGF) and the EGF receptor (EGFR) play an essential role in wound healing through the stimulation of epidermal and dermal regeneration (1). EGF induces dermal wound healing through stimulation, proliferation and migration of keratinocytes, endothelial cells and fibroblasts (2). Thus, topical administration of EGF has been used in various skin defects, such as skin grafts, venous ulcers and diabetic foot ulcers. A 29-year-old woman presented with a linear abrasion of 1× 10 cm2 area resulting from a fall on stairs (Figure 1). Primary closure was not considered because the width and the depth of the wound were not suitable for suturing and the margin was irregular. We decided to treat the wound with topical EGF to repair the skin defect. During treatment, 0⋅2 ml (100 mg) recombinant human EGF (50 mg/100 ml corresponding to 60 000 000 IU; Daewoong Pharmaceutical, Seoul, South Korea) was topically applied twice a day with hydrocolloid dressing (Duoderm CGF; ConvaTec, Woerden, the Netherlands) for 2 weeks. The wound had completely healed after 2 weeks, with only a linear scar remaining. In addition to wound healing, new hair growth was observed on the normal skin around the wound (Figure 2). There was no visible hair before the treatment, and the patient had not been treated previously with any depilation procedure on her legs. We surmised that growth of the new hair was induced by topical EGF, because there was no newly grown hair at any other site on the body, except for the periwound lesion where topical EGF was applied. In addition, the patient had never before experienced new growth of hair at the sites of previously healed wounds. That wound healing process can induce new hair growth is a natural concept, and there are few related papers in literature.