Please assess the completion status of the following clinical trial:

Trial Title: FLT-PET Imaging of Brain Tumors in Children

Study Design Characteristics:
- Allocation: NON_RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: DIAGNOSTIC
- Time Perspective: None
- Masking: SINGLE
- Phase: PHASE2
- Number of Arms: 3.0

Eligibility Criteria:
Inclusion Criteria:~* age 21 years or less~* capable of achieving imaging without need for sedation or anesthesia (typically age 8 years or greater, but there is no lower limit for age for eligibility)~* Karnofsky Performance Status of 50 or greater in subjects age 12 years or greater, for age less than 12 years a Lansky play scale of 50% or greater~* Patients receiving steroids and/or anti-seizure medications are eligible~Exclusion Criteria:~* clinically active infection~* pregnancy or breast-feeding~* serious intercurrent medical illness~* require emergency surgical intervention that would be inappropriately delayed by FLT-PET imaging

- Gender: ALL
- Minimum Age: None
- Maximum Age: 21 Years
- Healthy Volunteers: f

Study Arms:
- New diagnosis of brain tumor (Type: EXPERIMENTAL): In children with a new diagnosis of central nervous system tumor, a PET scan will be performed using \[18F\] FLT.
- Possible recurrent brain tumor (Type: EXPERIMENTAL): In children in whom there is concern for recurrent central nervous system tumor, a PET scan will be performed using \[18F\] PET.
- Brain tumor response to chemotherapy (Type: EXPERIMENTAL): In children with a newly diagnosed central nervous system tumor who will be treated with post-operative chemotherapy, a PET scan will be performed using \[18F\] FLT before the start and after two cycles of chemotherapy.~Despite much effort and working with referring physicians at multiple hospitals, enrollment in this arm remained low, and it seemed unlikely that meaningful enrollment would be accomplished. A revised study plan was submitted to the granting agency and FDA, and this arm was closed to further enrollment.

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