NRSTS2021, A Risk Adapted Study Evaluating Maintenance Pazopanib, Limited Margin, Dose-Escalated Radiation Therapy and Selinexor in Non-Rhabdomyosarcoma Soft Tissue Sarcoma (NRSTS)

Low, Intermediate and High-risk Surgery to remove tumor (standard of care)

Low, Intermediate and High-risk Radiation therapy is considered standard of care for patients with NRSTS who have positive tumor margins. However, the dose that will be given in this study is higher than what is usually given, therefore, the dose of radiation in this study is research. Radiation will start about 3 to 6 weeks after your surgery, depending on how quickly you recover from surgery. Radiation will be given daily (Monday through Friday) for about 5 to 6 weeks.

Intermediate and High-risk By mouth, either by tablet or a liquid suspension, 7 doses, days 1 to 7

Intermediate and High-risk Ifosfamide is a structural analogue of cyclophosphamide. Into the vein (IV) over about 3 hours, 3 doses, days 1, 2, and 3

Intermediate and High-risk An anthracycline antibiotic isolated from cultures of Streptomyces peucetius. Intermediate, High-risk Into the vein (IV) over about 1 hour, 2 doses, days 1 and 2

"High-risk Dosage and route of administration: Selinexor tablets for oral administration should be taken at approximately the same time each day without regards to meals.~Selinexor is a selective inhibitor of nuclear export (SINE). Selinexor specifically blocks XPO1-mediated nuclear export by forming a slowly reversible covalent bond with the nuclear export protein XPO1 By mouth, either by tablet or a liquid suspension, 1 dose and day 3"