This study enrolls patients that have been diagnosed with acute leukemia associated with a KMT2A (MLL) gene rearrangement (referred to as KMT2Arearranged, or KMT2A-R). The KMT2A-R leukemia has come back after treatment (relapsed) or is not responding to treatment (it is refractory). This study involves taking a study drug called SNDX-5613. The study is divided into two phases: one in which the study drug is given in combination with chemotherapy and a phase where the study drug is given alone. The purpose of the study is to test the safety of the study drug with chemotherapy, and how well the treatment regimen works for infants and young children with relapsed or refractory KMT2A-R leukemia.

This study involves an investigational cellular therapy called Afamitresgene Autoleucel. The overall goal of this study is to find out how safe and effective this cellular therapy is in treating people that have been diagnosed with synovial sarcoma, malignant peripheral nerve sheath tumors (MPNST), neuroblastoma or osteosarcoma that has grown or returned after being treated.

This study involves taking a study drug called BA3011. The overall goal of this study is to see if BA3011 is a possible treatment for patients with sarcoma.

This study enrolls patients with newly diagnosed differentiated thyroid cancer (papillary thyroid cancer or follicular thyroid cancer) that has spread to the lungs and has a genetic mutation called and NTRK fusion. The study involves taking a study drug called larotrectinib for approximately 6 months prior to receiving radioiodine therapy (RAI). The overall goal of this study is to find out if taking the study drug before RAI works better than receiving RAI alone (the usual standard of care treatment).

This study involves taking a study drug called lurbinectedin. The overall goal of this study is to see if different doses of lurbinectedin are safe and effective at treating children and young adults with recurrent or relapsed solid tumors, including Ewing Sarcoma.

This study involves taking a study drug called Lutathera. The overall goal of this study is to see if Lutathera is safe in adolescent subjects with either a gastroenteropancreatic neuroendocrine tumor (GEP-NET), or a pheochromocytoma and/or paraganglioma (PPGL). This study will also look at the levels of radioactivity after Lutathera administration.

The goal of this observational study is to describe the safety and effectiveness of larotrectinib in patients with locally advanced or metastatic TRK fusion cancer for whom a decision to treat with larotrectinib has been made before enrollment. This study will enroll participants with any tumors harboring the NTRK gene fusion including Soft Tissue Sarcomas, Central Nervous System, Melanoma, and Thyroid cancers.

This study involves taking a study drug called asciminib. The overall goal of the study is to find out how safe and effective the study drug is in treating people that have been diagnosed with Chronic Myeloid Leukemia (CML) and have not responded to treatment.

The purpose of the Phase 2 portion of this study is to evaluate the safety and efficacy of the study drug called palbociclib when given in combination with two other drugs (temozolomide and irinotecan) in patients with Ewing sarcoma and when given in combination with topotecan and cyclophosphamide in patients with neuroblastoma.

This study enrolls patients with refractory, progressive, or relapsed solid tumors. The purpose of this study is to find out whether a drug called PEEL-224 ("the study drug") is safe and effective when given as monotherapy (a drug given by itself) and as part of a combination therapy together with other chemotherapy drugs.