Efficacy and safety of proton beam therapy for rhabdomyosarcoma: a systematic review and meta-analysis

Objective This study aimed to evaluate and conduct a meta-analysis on the efficacy and safety of proton beam therapy (PBT) for rhabdomyosarcoma (RMS). Methods We searched for articles using PubMed, Embase, Cochrane Library, and Web of Science databases from their inception to December 22, 2022. Two researchers independently screened literature and extracted data. Statistical analyses were performed using STATA version 14.0. Results We got 675 candidate articles, of which 11 studies were included in our study according to the inclusion and exclusion criteria. Of the 544 RMS patients who received PBT. The local control (LC) rate at 1, 2, 3, 4, and 5 years were 96% (95% confidence interval (CI) 0.91–1.01), 93% (95% CI 0.86–1.00), 78% (95% CI 0.71–0.85), 85% (95% CI 0.78–0.92), and 84% (95% CI 0.74–0.95), respectively. The progression-free survival (PFS) rate at 1, 2, 3, 4, and 5 years were 82% (95% CI 0.72–0.92), 73% (95% CI 0.61–0.84), 63% (95% CI 0.47–0.79), 64% (95% CI 0.54–0.74), and 76% (95% CI 0.59–0.94), respectively. The overall survival (OS) rate at 1, 2, 3, 4, and 5 years were 93% (95% CI 0.86–1.00), 85% (95% CI 0.76–0.95), 80% (95% CI 0.63–0.96), 71% (95% CI 0.62–0.80), and 82% (95% CI 0.71–0.94), respectively. Acute and late toxicities were mainly grades 1 to 2 in all studies. Conclusion As an advantageous RT technique, PBT is an emerging option for patients with RMS, particularly children and adolescents patients. The data showed that PBT is a feasible, safe, and effective modality for RMS, showing promising LC, OS, PFS, and lower acute and late toxicities. PROSPERO registration number : CRD42022329154.