Potentials for implementing pressure-controlled jet injection in management of keloids with intralesional 5FU and corticosteroids

Background: Needle-free jet injection implements kinetic energy of liquid jet for transcutaneous delivery of drugs into soft tissues. Combination therapy of intralesional 5-fluorouracil and triamcinolone offers efficacious treatment for keloids with a reduced adverse effect of the drug monotherapy. This study evaluates safety and efficacy of the drug combination administered to keloid scars via intralesional jet injections. Methods: A retrospective analysis of the keloid treatments was performed. Efficacy was assessed by reviewing pre- and post-treatment scores of the Vancouver Scar Scale (VSS) and Patient and Observer Scar Assessment Scale (POSAS) and by comparing baseline and photographs taken 3 months after the treatments. Safety and tolerability were collected and analyzed. Results: Twenty-one subjects (M/F = 11/10) with 39 keloids received the treatments. Treatments were well-tolerated by all patients at mean injection pain of 2.0 ± 1.0 per Numeric Pain Rating Scale (NPRS). Self-resolved lesion ulceration was observed in 4 patients. Post-treatment evaluation demonstrated a 53% decrease in total VSS score (P < 0.05) and in all sub-categories. Mean patient score of POSAS decreased in the color, stiffness, thickness, and irregularity components. Pain and pruritus lessened by 69% and 79% (P < 0.05 in both), respectively, among the patients with complaints prior to the treatment. Independent reviewers reported an average 51%-75% reduction in keloids. Conclusions: Improved appearance of keloids and symptomatic relief was achieved by intralesional administration of combined 5-fluorouracil and corticosteroid through the high-pressure jet injections. The synergy between the drug combination and the jet physical impact provided clinical effect.