In this research study, we are looking to study the side effects from the use of proton radiation in treating people with low-grade gliomas that are recommended radiation treatment. We expect response of the tumors to be the same with proton radiation as compared to standard 3D conformal radiation therapy, but also expect less side effects from radiation.

• Participants will receive radiation therapy for 6 weeks, given in daily doses, Monday through Friday, for a total of 30 treatments.
• A medical history and physical examination will be performed prior to the start of radiation treatment, weekly during the 6 weeks of radiation and after the finish of radiation performed at 3 and 6 months and then annually for 5 years.
• Hormonal function tests will be taken prior to the start of radiation treatment and after the finish of radiation treatment at 3 and 6 months, and annually for five years to assess the participants hormonal functions as they relate to the pituitary gland's function.
• A brain MRI will be performed prior to the start of radiation treatment and then performed at 3 and 6 months after radiation treatment then annually for 5 years.
• A neurocognitive exam will be performed prior to the start of radiation therapy, a limited exam 6 months after the completion of radiation therapy, and a complete exam annually for 5 years.
• Quality of Life and Emotional Well-Being Questionnaires will be done before radiation begins, 2 months after radiation treatment, 6 months after radiation treatment and then annually for 5 years.

Inclusion Criteria:

• Histologically confirmed low-grade gliomas, WHO classification II/IV or equivalent low grade histology, including protoplasmic, fibrillary, gemistocytic astrocytomas, and mixed variants such as oligoastrocytomas
• Must have at least one of: (1) progressive or recurrent disease as defined by imaging, (2) persistence or progression of debilitating neurological symptoms, or (3) at risk of early progression as defined by either (a) age of 40 or older or (b) MIB-1 of 3% or greater
• KPS of 70 or greater
• 18 years of age or older
• Surgical and medical/chemotherapeutic interventions are per physician's discretion and are acceptable
• Must be able to speak and comprehend English

Exclusion Criteria:

• Other baseline neurocognitive or emotional disorders or deficits, including but not limited to head injury, CVA, TIA, or other cerebral insults with residual neuropsychiatric deficits, psychiatric disorders, learning disabilities, HIV positivity or other medical conditions at high risk of causing neurocognitive decline or emotional instability
• Prior history of cranial irradiation
• Pregnancy at the time of radiation treatment
• Unable to undergo MRI scans (e.g., embedded ferromagnetic metal or pacemakers)
• Comorbid illness or reason to suggest a life expectancy of less than 5 years

All 20 baseline participants were included in analysis.

Up to 5 years post RT