Topical Treatments for Keloids and Hypertrophic Scars Lack Widespread Acceptance

hypertrophic scar
Close up of cyanotic keloid scar caused by surgery and suturing, skin imperfections or defects. Hypertrophic Scar on skin, dermatology and cosmetology concept.
Available evidence on the best treatment modality for scarring is reviewed.

Treatment for a keloid scar with clobetasol propionate ointment under occlusion with silicone gel sheet (SS) for 6 months resulted in Vancouver Scar Scale reduction of 60%, no side effects, and significant reduction in discomfort in an 8-year-old girl. Lack of evidence and poor experimental outcomes have led to a lack of widespread adoption of topical treatments for keloids and hypertrophic scars, according to findings from a review and case study published in the British Journal of Dermatology.

An 8-year-old girl with a painful keloid scar following a history of varicella zoster virus and significant needle-phobia led researchers to review topical treatment options.

They initiated a search of the Clinical Trials Registry and the Embase and MEDLINE databases from inception through January 7, 2022 revealing multiple studies with design and method heterogeneity and subsequently did not perform meta-analysis. Selection bias, detection and performance bias, and a prevalence of incomplete outcome data was noted with the Cochrane Risk of Bias tool.

They found 3 systematic reviews of randomized controlled trials (RCTs) with topical treatment arms. A single review showed 2000 patients from 29 RCTs, only 3 of which included a topical (silicone) treatment arm. They noted triamcinolone acetonide (TAC) combined with botulinum toxin A therapy effective and tolerated, with the greatest efficacy among any combination or monotherapy treatment. Another review showed only 2 of 22 RCTs presented a topical treatment arm, and that TAC combined with 5-fluorouracil may be the most efficacious therapy among intralesional treatments.

Investigators noted another review compared SS with other conservative treatments in RCTs, quasi-RCTs, and controlled clinical trials. The conclusion of these researchers was that SS effects were uncertain.

Current investigators found 6 additional RCTs using 1 or more of the Vancouver Scar Scale, visual analogue scale, or Patient Observer Scar Assessment Scale. Most of these studies compared topical treatments vs other topicals or placebo, and 1 examined clobetasol propionate 0.05% under silicone dressing vs TAC. The most frequent topical treatment assessed was SS. Studies that included SS and placebo treatment arms showed some positive statistically significant differences, it was noted. Very few studies mentioned adverse events, and those mentioned were mild (pruritus, skin rash, occasional irritation, maceration and dryness). A single study reported pustular eruptions.

Few studies included patients under 18 years of age, and none focused on pediatric patients.

Current reviewers believe SS a safe, well-tolerated topical treatment, preferred first-line therapy, mitigating discomfort associated with other treatments like TAC. However, while acknowledging many studies showed scar improvement following topical treatment (SS most commonly) they found “the heterogeneity of outcome measures and diversity of topical treatments undermined a definitive recommendation for choice of topical treatment.”

In their case study, “treatment with clobetasol propionate ointment under occlusion with SS led to 60% reduction in Vancouver Scar Scale after 6 months, together with significant reduction of discomfort, without side effects.” Investigators found the lack of prevalence of topical treatments for hypertrophic and keloid scars argues for more significant research and clinical studies aimed at pain-free, cost-effective topical treatment, particularly in pediatric patients.

Reference

Ghadiri SJ, Kloczko E, Flohr C. Topical treatments in the management of keloids and hypertrophic scars: a critically appraised topic. Br J Dermatol. Published online August 17, 2022. doi:10.1111/bjd.21824