Imiquimod to prevent keloid recurrence postexcision: A systematic review and meta-analysis

Imiquimod 5% cream, an immune response modifier capable of inducing IFN-α, TNF-α, and interleukins 1, 6, and 8. It was approved for use in the management of genital and perianal warts and soon embraced as a method to diminish the recurrence of keloids postexcision. A previous meta-analysis included four studies. This meta-analysis is part of a larger systematic review project on the effect of moisturizers on scars. It was conducted following an a priori protocol and the guidance of the Joanna Briggs Institute. Databases searched included PubMed, CINAHL, Embase, and Web of Science. After screening and critical appraisal, subgroup meta-analysis on excision method and location of the keloid was conducted using the Miller approach for proportional meta-analysis and a random effects model. Seven studies, including 77 participants and 82 keloids were included. Meta-analysis revealed a recurrence rate of 39% (95% CI = 8.474.4%; I² = 87.5%) following application of Imiquimod postexcision. The use of primary excision or tangential excision did not alter the outcome. For analysis based on the location of the keloid scar, earlobe keloids had a recurrence rate of 5.4% (95% CI = 0-21.7%; I² = 52.9%). For keloids excised from other areas (predominantly on the trunk) recurrence rate was higher, at 76.8% (95% CI = 36.1-100%). For keloids, Imiquimod application postexcision results in highly variable recurrence rates. There is very low certainty in the effect of Imiquimod and it therefore is not recommended as a treatment option.