Preliminary Analysis Of The Mutational Landscape Of Non-Rhabdomyosarcoma Soft Tissue Sarcoma: A Children'S Oncology Group Study.

10510 Background: Pediatric non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) represent a histologically diverse group of more than 20 tumor subtypes, including synovial sarcoma, liposarcoma, and malignant peripheral nerve sheath tumors. Unlike children with rhabdomyosarcoma, systemic chemotherapy has failed to improve survival for those with NRSTS. Of the nearly 50% with intermediate or high-risk disease, only 50% and 15%, respectively, are expected to survive. Methods: To determine more effective, targeted therapies, we analyzed 55 archived formalin-fixed paraffin-embedded (FFPE) cases of NRSTS using Sequenom’s MassARRAY system to interrogate 296 unique “actionable” mutations (mutations that can be targeted by currently available drugs) in 33 oncogenes and tumor suppressor genes. We also analyzed 15 of the samples for copy-number variation and 74 additional “actionable” mutations in 9 cancer-associated genes using the Affymetrix OncoScan platform. Results: Using MassARRAY, we found 11 mutations in 8 NRS...