The Use of Mitomycin C and Keloid Scar Recurrence

Introduction: Keloids are fibrotic lesions that are a result of an abnormal wound-healing process that lacks control of the mechanisms that regulate tissue repair and regeneration. Recurrence following excision is very common. The proliferation of normal tissue-healing processes results in scarring that enlarges well beyond the original wound margins. The pathogenesis of keloid is not completely understood. Russell and colleagues found that TGF-ß reduced growth stimulation by epidermal growth factor in normal fibroblast cultures while enhancing growth of keloid fibroblasts. Responses to hydrocortisone were also different. The growth rate of normal cells was increased, whereas that of keloid fibroblasts was either unaffected or suppressed. Many treatment modalities for keloids have been tried with variable amounts of success. Despite the wide range of available treatments, recurrence rates typically remain in the 50%-70% range. We reviewed the rate of recurrence of keloids following the use of Mitomycin C at our institution. Materials and Methods: We retrospectively reviewed patients that underwent keloid excision at our institution between January 2004 and December 2009. Patients were placed into one of two groups 1) Excision and application of Mitomycin C 2) Excision without additional treatment. Mitomycin C is a DNA synthesis inhibitor. It selectively inhibits synthesis of DNA and suppresses cellular RNA and protein synthesis at high concentrations. Following keloid excision, Mitomycin C at a concentration of 0.4 mg/ml was applied to the wound bed for 5 minutes prior to wound closure. Immediate outcomes such as post operative complications and recurrence of the keloid scar were compared to a control group of patients without mitomycin application. All patients were followed for an average of 10 months (Range 6 months - 22 months). Statistical analysis was done using Student t-test for continuous data and chi-square analysis for categorical data. Results: A total of 40 patients (22 female and 18 male) ranging from 7 to 60 years were enrolled in this study. Recurrence of keloids was seen in 3 (13%) of the 23 patients that underwent Mitomycin C treatment when compared to 11 (65%) of 17 patients without the treatment (p=0.002). Postoperative complications were similar (p=0.89) in both groups. Conclusion: Mitomycin C, when applied to the wound bed at a concentration of 0.4 mg/mL, reduces the incidence of keloid scar recurrence.