Current Perspective: The Role of Liquid Biopsy in Diagnosis and Management of Pediatric Rhabdomyosarcomas (RMS)

Rhabdomyosarcoma is the third most common extracranial solid tumor of childhood. Despite extensive research over the preceding decades, prognosis in children with metastatic or recurrent disease remains very poor with overall 5-year survival rates under 20%. Liquid biopsy is emerging as an effective, clinically applicable, noninvasive adjunct to conventional oncological management. To date, liquid biopsy has predominantly been applied in the field of adult oncology. Translation into pediatric malignancies, including rhabdomyosarcoma, remains at an early stage with small cohort studies addressing feasibility and technique optimization. This narrative review addresses the current literature in the field of liquid biopsies in rhabdomyosarcoma considering a variety of circulating biomarkers including ctDNA, mRNA, miRNA, proteins, and tumor cells. Liquid biopsies have the potential to revolutionize real-time tumor monitoring and personalized oncological treatment. The results of further large-scale prospective clinical trials in rhabdomyosarcoma are necessary to enable successful integration into standard clinical care.