A systematic review and network meta-analysis of the effectiveness of sclerotherapy for venous malformation

Abstract

Objective: Sclerotherapy for venous malformation has been widely used; however, no guidelines are available to assess the effectiveness of different sclerotherapy agents. We conducted a systematic review and network meta-analysis to investigate the effectiveness of sclerotherapy agents for venous malformations.

Methods: Three electronic databases were searched from their inception (1950) to April 29, 2021. Studies comparing the effectiveness of different sclerotherapy agents were included. The risk of bias within and across studies was assessed. Pairwise meta-analyses were conducted, followed by a network meta-analysis. We also assessed inconsistency and publishing bias using various approaches.

Results: Seven studies with 547 patients in six arms were included in the present study. We defined the response and complete response as two separate outcomes. Significant differences were observed in four comparisons with respect to the response (ethanol vs bleomycin, ethanol vs polidocanol, ethanol vs sodium tetradecyl sulfate, polidocanol vs sodium tetradecyl sulfate). No statistically significant differences were found in the other comparisons. The evidence network revealed that for the response outcome, ethanol ranked first, followed by pingyangmycin, polidocanol, sodium morrhuate, bleomycin, and, finally, sodium tetradecyl sulfate. For the complete response outcome, pingyangmycin had the best results, followed by sodium morrhuate, polidocanol, ethanol, bleomycin, and, finally, sodium tetradecyl sulfate. Major complications, such as facial nerve palsy, serious local swelling, and necrosis, had occurred mostly in the ethanol group and rarely in the other groups. Because of the limited data, no further analysis of major complications was conducted. Our confidence in the comparisons and rankings was low. We found no verified inconsistency or publishing bias in the present study using the existing approaches.

Conclusions: Ethanol showed a significantly better response statistically compared with the other agents. However, ethanol had also resulted in the highest incidence of complications. Pingyangmycin showed the second-best response, best complete response, and a low rate of complications, respectively. Overall, pingyangmycin achieved excellent performance and balance in terms of the different outcomes. However, they could not be adequately recommended from the available data. More superior trials, especially randomized controlled trials, are needed in the future.

Keywords: Network meta-analysis; Sclerotherapy; Systematic reviews; Vascular malformations; Venous malformations.