A Two-part Phase IIb Trial of Vigil (Bi-shRNAfurin and GMCSF Augmented Autologous Tumor Cell Immunotherapy) in Ewing's Sarcoma

Tissue Procurement Inclusion Criteria: Patients will be eligible for tissue procurement for the Vigil manufacturing process, if they meet all of the following criteria: * Histologically confirmed Ewing's Sarcoma Family of Tumors (ESFT) * Age ≥2 years * Estimated survival ≥ 6 months * Evidence of EWS translocation by FISH or RT-PCR or Next Generation Sequencing (NGS) Metastatic disease * Refractory or intolerant to ≥ 2 lines of systemic chemotherapy (Part 1) or Refractory or intolerant to at least 1 line of systemic chemotherapy (Part 2) * Planned standard of care surgical procedure (e.g., tumor biopsy or palliative resection or thoracentesis) and expected availability of a cumulative mass of \~10-30 grams tissue ("golf-ball" size) or pleural fluid estimated volume ≥ 500mL (must be primary tap) for immunotherapy manufacture * Tumor intended for immunotherapy manufacture is not embedded in bone and does not contain luminal tissue (e.g., bowel, ureter, bile duct) * Ability to understand and the willingness to sign a written informed consent document for tissue harvest Tissue Procurement Exclusion Criteria: Patients meeting any of the following criteria are not eligible for tissue procurement for the Vigil manufacturing: * Medical condition requiring any form of chronic systemic immunosuppressive therapy (steroid or other) except physiologic replacement doses of hydrocortisone or equivalent (no more than 30 mg hydrocortisone or 10 mg prednisone equivalent daily) for \< 30 da…