Efficacy of Laser Interstitial Thermal Therapy in Young Persons With Low-grade Glioma

Inclusion Criteria: * Participants must have recurrent or progressive pediatric LGG who have received at least one prior treatment. Prior treatment may include surgery alone and/or systemic therapy. * Participants must have histologically confirmed LGG that is recurrent or progressive after prior treatment and determined to be a candidate for LITT by central review. All patients will undergo central review prior to LITT. Any number of previous recurrences are permissible provided the participant meets other enrollment criteria. * Tumor size: up to 5 cm in largest dimension not including any cystic component. Larger tumors will need to be discussed with the study team. Additional adjunctive interventions such as cyst aspiration prior to or concurrent with a LITT procedure is allowed at the treating surgeon's discretion. Tumor location: Tumors must be located in areas of the brain or central nervous system that are accessible and considered safe for LITT, as determined by central review. * Suprasellar gliomas not arising from the optic pathway are eligible. * Multifocal or metastatic LGGs are eligible, provided that the growing lesions are suitable for LITT. * Exophytic brainstem lesions, which are more accessible and present a lower risk, may be eligible for LITT. * A patient with stable leptomeningeal disease and a separate growing lesion suitable for LITT is eligible for the study. * Prior Therapy: Participants may have had LITT for other medical indications, provided …