Current State-of-the-Art Systemic Therapy for Pediatric Soft Tissue Sarcomas

Pediatric soft tissue sarcomas (STS) are a heterogeneous group of tumors. Rhabdomyosarcomas (RMS) are the most common histologic subtype, while synovial sarcomas and undifferentiated sarcomas are among the more common non-rhabdomyosarcomatous soft tissue sarcomas (NRSTS) encountered. While the survival outcome for certain groups of RMS patients is quite good, the prognosis for those with alveolar histology or those with metastatic or relapsed disease remains dismal. Also, the response rate for some NRSTS to conventional chemotherapy is suboptimal. Thus increased understanding of involved molecular pathways, such as the insulin growth factor and mammalian target of rapamycin pathways, may indicate potential targets for therapy. In addition, immunotherapy-based approaches that include both non-specific activation with interleukins as well as targeted tumor antigen specific T lymphocytes are emerging avenues in the treatment of children with soft tissue sarcomas.