Please assess the completion status of the following clinical trial:

Trial Title: Treatment of Patients With Newly Diagnosed Medulloblastoma, Supratentorial Primitive Neuroectodermal Tumor, or Atypical Teratoid Rhabdoid Tumor

Study Design Characteristics:
- Allocation: NON_RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: NONE
- Phase: PHASE3
- Number of Arms: 2.0

Eligibility Criteria:
DISEASE CHARACTERISTICS:~* Histologically confirmed diagnosis of 1 of the following:~  * Medulloblastoma~ * Supratentorial primitive neuroectodermal tumor (PNET)~ * PNET variants (ependymoblastoma, pineoblastoma, CNS neuroblastoma)~ * Atypical teratoid rhabdoid tumor (ATRT)~* Definitive surgery for CNS tumor within the past 31 days~* Meets one of the following risk criteria:~  * Average-risk disease~    * Localized disease with no overt evidence of invasion beyond the posterior fossa (or supratentorial compartment for PNET or ATRT) by intraoperative observations of the neurosurgeon AND postoperative CT scan or MRI~   * T4 disease eligible if all of the following are true:~      * Gross total resection determined by intraoperative observations of the neurosurgeon AND postoperative CT scan or MRI~     * Residual tumor or imaging abnormality whose size is \< 1.5 cm\^2~     * No evidence of CNS or extraneural metastasis by MRI of the spine (with and without contrast agent) or CT-based myelogram AND by cytologic examination of the lumbar cerebral spinal fluid (CSF) 14-28 days after surgery~   * Brain stem invasion allowed in the absence of residual tumor (tumor \< 1.5 cm\^2 by imaging)~ * High-risk disease meeting one of the following criteria:~    * Metastatic disease within the neuraxis (i.e., evidence of subarachnoid dissemination by imaging and/or cytologic examination of CSF)~   * Presence of residual disease \> 1.5 cm\^2 at the primary site after surgery~PATIENT CHARACTERISTICS:~Age~* 3 to 21 at diagnosis~Performance status~* Lansky 30-100% (\< 10 years old)~* Karnofsky 30-100% (≥ 10 years old) (except for posterior fossa syndrome)~Life expectancy~* Not specified~Hematopoietic~* Hemoglobin \> 8 g/dL~* WBC \> 2,000/mm\^3~* Absolute neutrophil count \> 500/mm\^3~* Platelet count \> 50,000/mm\^3~Hepatic~* ALT \< 5 times normal~* Bilirubin \< 3.0 mg/dL~Renal~* Creatinine \< 2.0 mg/dL OR~* Creatinine clearance \> 70 mL/min~Other~* Not pregnant or nursing~* Negative pregnancy test~* Fertile patients must use effective contraception~PRIOR CONCURRENT THERAPY:~Biologic therapy~* Not specified~Chemotherapy~* No prior chemotherapy~Endocrine therapy~* Prior corticosteroid therapy allowed~Radiotherapy~* No prior radiotherapy~Surgery~* See Disease Characteristics

- Gender: ALL
- Minimum Age: 3 Years
- Maximum Age: 21 Years
- Healthy Volunteers: f

Study Arms:
- Stratum 1 (high-risk group) (Type: EXPERIMENTAL): Patients undergo craniospinal radiotherapy once daily 5 days a week for 6 weeks. Six weeks after the completion of radiotherapy, patients receive high-dose chemotherapy followed by autologous stem cell transplantation (SCT) and filgrastim (G-CSF) with post-transplantation vincristine. High-dose chemotherapy and autologous SCT repeat every 4 weeks for 3 additional courses in the absence of unacceptable toxicity.~Interventions: vincristine, cisplatin, cyclophosphamide, autologous hematopoietic stem cell transplantation, filgrastim, radiation therapy
- Stratum 2 (average-risk group) (Type: EXPERIMENTAL): Patients undergo craniospinal radiotherapy as in stratum 1, but at a lower dose. Patients receive high-dose chemotherapy, autologous SCT, G-CSF, and post-transplantation vincristine as in stratum 1.~Interventions: vincristine, cisplatin, cyclophosphamide, autologous hematopoietic stem cell transplantation, filgrastim, radiation therapy

Based on this trial design, predict the completion outcome and termination type (if applicable).