Therapeutic methods and effect on keloid and hypertrophic scars: a systematic review

Background Keloids and hypertrophic scars are fibroproliferative disorders with high recurrence rates, lacking a definitive treatment standard. This review systematically evaluates current therapies and their effectiveness in treating keloid and hypertrophic scars. Method The inclusion criteria were based on the population, intervention, comparator, outcomes, and study design (PICOS) framework. Electronic searches through April 2025 across databases such as PubMed, EMBASE, Cochrane Library, and Web of Science used keywords such as ‘keloid’, ‘occlusive dressings’, and ‘imiquimod’, among others. Meanwhile, we used the keywords ‘Antigens, CD’ and ‘MicroRNAs’ to search for molecular mechanisms associated with keloid and hypertrophic scars. The Risk of Bias 2 (RoB2) and Methodological Index for Non-Randomized Studies (MINORS) checklists were used to assess the quality of the included studies and potential bias. Results This study synthesizes findings from 162 studies, exploring a range of treatments including monotherapies and combination therapies, such as local corticosteroid injections, optical therapy, radiation therapy, 5-fluorouracil (5-FU) therapy, bleomycin therapy, verapamil therapy, excision surgery, cryotherapy, and topical treatments, as well as various multi-drug regimens. It also examines innovative therapies such as stem cells and RNA microneedles. Technological developments continue to expand the range of available interventions. Treatment strategies increasingly emphasized combination therapies that integrate intralesional corticosteroids, surgical excision, laser modalities, and radiotherapy, demonstrating superior outcomes compared with single-modality approaches, particularly in reducing recurrence, prolonging therapeutic benefit, and improving patient prognosis. Conclusion Sole treatments and inadequate therapy are major risk factors for recurrence. Anti-fibroblast growth strategies are crucial, aside from physical interventions. Despite the lack of an established gold standard, corticosteroid and excision therapies remain critical benchmarks for evaluating new treatments.