Abstract Purpose To review the available evidence on the effectiveness and safety of bleomycin electrosclerotherapy (BEST) for slow-flow vascular malformations. Materials and Methods A systematic review was conducted according to PRISMA guidelines, with a protocol registered in PROSPERO. Five databases were searched, supplemented by citation tracking, to identify peer-reviewed studies reporting clinical outcomes of BEST for slow-flow vascular malformations. Single-patient case reports were excluded. Two authors independently extracted data and assessed risk of bias. Results Ten studies were included, with a total of 401 patients and 416 lesions. Seven studies were retrospective, three were prospective, and one was comparative. Any symptom improvement was reported in 62–100% of patients; however, outcome definitions and assessment methods varied substantially across studies, limiting direct comparability. Any size reduction was reported in 83–100% of lesions, based on clinical and imaging-based assessments, including volumetry. Serious adverse events were uncommon, and no systemic toxicity was reported. All non-randomised studies had serious risk of bias. Conclusion BEST appears promising for selected slow-flow vascular malformations. However, evidence is limited by methodological heterogeneity and high risk of bias, and treatment decisions should remain individualised and based on multidisciplinary evaluation. Graphical Abstract
Gehr et al. (Mon,) studied this question.