The safety and efficacy of intralesional triamcinolone acetonide for keloids and hypertrophic scars: A systematic review and meta-analysis

Triamcinolone acetonide (TAC) is widely used for hypertrophic scars and keloids; however, TAC has variable efficacy and safety in different individuals.To evaluate the efficacy and safety of intralesional TAC for treatment of hypertrophic scars and keloids.Searches of PubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov prior to 25 March 2020.Randomized controlled trials in English that compared TAC with a placebo or other medications that are commonly used for intralesional injection in hypertrophic scars and keloids.Primary outcomes were reduction in scar height, vascularity, pliability, pigmentation, total scores on the Vancouver Scar Scale (VSS) or patient and observer scar assessment scale (POSAS), telangiectasia, and skin atrophy. Secondary outcomes included overall scar improvement.Fifteen trials met the inclusion criteria. In the short term, TAC was associated with a significant improvement in vascularity (MD: -0.22, 95% CI: -0.42 to -0.02) and pliability (MD: -0.25, 95% CI: -0.44 to -0.06) compared to verapamil. In the medium term, compared to TAC, 5-FU showed a significant improvement in scar height (SMD: 0.95, 95% CI: 0.15-1.75), while TAC led to a significant improvement in vascularity compared to 5-FU (MD: -0.45, 95% CI: -0.76 to -0.14). Compared to TAC, TAC+5-FU showed a significant improvement in pliability (SMD: 0.98, 95% CI: 0.17-1.78) and pigmentation (MD: 0.45, 95% CI: 0.12-0.78). Botulinum toxin type A resulted in significantly better pliability (SMD: 1.99, 95% CI: 0.98-3.00) compared to TAC. In the long term, compared to TAC, 5-FU led to a significant improvement in scar height (MD: 0.55, 95% CI: 0.17-0.93), but significantly less vascularity (MD: -0.35, 95% CI: -0.65 to -0.05). Compared to TAC, TAC+5-FU produced a significant improvement in scar height (MD: 1.50, 95% CI: 1.12-1.88), pliability (MD: 0.45, 95% CI: 0.10-0.80), and pigmentation (MD: 0.55, 95% CI: 0.24-0.86).TAC may be beneficial for the short-term treatment of hypertrophic scars and keloids; however, 5-FU, 5-FU+TAC, and verapamil may produce superior results for medium- and long-term treatments. TAC injections at concentrations of 20 mg/ml or 40 mg/ml are more likely to result in skin atrophy compared to 5-FU or verapamil, and are more likely to cause telangiectasia than 5-FU, 5-FU+TAC, or bleomycin.