Embryonal Tumor With Multilayered Rosettes

PRIMARY OBJECTIVES I. To determine the six-month progression-free survival (PFS6) of participants with newly diagnosed, gross-totally resected, non-metastatic ETMR, treated using a regimen of induction chemotherapy and early focal radiotherapy (Cohort 1) SECONDARY OBJECTIVES I. To determine the two-year progression-free survival (PFS) and overall survival (OS) of participants with newly diagnosed, gross-totally resected, non-metastatic ETMR (Cohort 1). II. To determine the two-year progression-free survival (PFS) and overall survival (OS) of participants with newly diagnosed, gross-totally resected, non-metastatic ETMR (Cohort 2). III. To determine the two-year progression-free survival (PFS), overall survival (OS) and objective response rate of participants with newly diagnosed, incompletely resected and/or metastatic ETMR (Cohort 3A and 3B) EXPLORATORY OBJECTIVES: I. To validate the utility of a liquid miRNA biomarker in blood and Cerebral spinal fluid (CSF) as a correlative marker of a participant's disease status. II. To better define the genomic landscape of ETMR. OUTLINE: Participants with newly diagnosed ETMR will obtain either gross total, or sub-total resection surgery prior to enrollment. After surgery, participants will be assigned to 1 of 4 possible cohorts: Cohorts 1 and 2: Participants with newly diagnosed, gross-totally resected, non-metastatic ETMR. Cohorts 3A and 3B: Participants with newly diagnosed, incompletely resected and/or metastatic ETMR. Participants will be assessed for survival outcomes for up to 2 years. Follow-up procedures are to be captured under the PNOC COMP protocol. Participants will be followed under the Pediatric Neuro-Oncology Consortium (PNOC) COMP protocol until death or withdrawal from study.