Update on Keloid Management: Clinical and Basic Science Advances

Abstract

Background: Keloids are benign, fibroproliferative lesions that represent abnormal healing resulting in excessive fibrosis. They are composed of mainly type III (early) or type I (late) collagen. Some of the symptoms include pruritus, tenderness, and pain. Often, they are very difficult to treat and prevent from recurrence. In contrast to hypertrophic scars, keloids extend beyond the margin of the wound.

The problem: There is very limited evidence on the best wound management for minimizing scarring. Multiple available therapeutic modalities have been used for the treatment of keloids; however, high-recurrence rates continue to be reported. Unsuccessful treatment of keloids leads to psychological impact on the patients and increased economic burden.

Basic/clinical science advances: Currently, there are biological and antineoplastic agents that can potentially treat and prevent excessive scar formation. Some of them have been used as "off label" therapies, and others are still in the experimental phase such as interferon alpha (IFN-α), imiquimod, and transforming growth factor beta1 (TGF-β1). The use of IFN-α2b showed 18% recurrence rate when applied to postsurgical excised keloids. Imiquimod 5% can lower recurrence rate on postshaved keloids to 37.5% at 6-month and to 0% at a 12-month follow-up period. TGF-β1 oligonucleotides have shown effective and long-lasting inhibition of TGF-β-mediated scarring in vitro as well as in animal models. Daily injections of neutralizing antibodies against TGF-β1 and -β2 have shown successful reductions in scarring.

Conclusion: Latest discoveries in the use of novel agents suggest therapeutic alternatives for the prevention of recurrences of hypertrophic scars and postexcision keloid lesions.

Brian Berman, MD, PhD

Figure 1.

Imiquimod's immune modification: cascade of effects.