Evidence of invasive and noninvasive treatment modalities for hypertrophic scars: A systematic review

Currently, there are various therapeutic approaches to reduce hypertrophic scarring; however, there is no standard evidence-based treatment protocol. Hence, a systematic review was performed to obtain a summary of the latest clinical trials to evaluate evidence for the treatment of hypertrophic scars. The review protocol was registered and approved by PROSPERO (CRD42015027040). PubMed and Web of Science were searched using predefined MeSH-Terms to identify studies published within the last 10 years regarding treatment for hypertrophic scars. Exclusion criteria included a level of evidence (LoE) lower than I, nonhuman in vivo studies, in vitro studies, studies on keloids, literature reviews, and non-English articles. The literature search identified 1,029 unique articles, whereas 6 articles were prospective, randomized, blinded, controlled clinical trials with a LoE I, and were thus included in the systematic analysis. Three clinical trials evaluated silicone products and pressure garments, and the other three studies investigated the efficacy of intralesional injections of triamcinolone (TAC), 5-Fluorouracil (5-FU) combined with TAC as well as the additional irradiation with a 585 nm pulsed-dye laser (PDL). Intralesional injections revealed significant improvements of the scar quality in terms of height, thickness, erythema, and pigmentation. Pressure garments showed favorable results but there was no evidence that silicone products were able to improve the scar quality. The systematic review demonstrated that there are just a few clinical trials with a LoE of I. Consequently, evidence is still lacking especially for noninvasive treatment regimens for hypertrophic scars. Intralesional injections of 5-FU mixed with a low dose of TAC can be seen as most appropriate treatment modality. Prospective clinical trials to determine the efficiency of silicone products are warranted.