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HALGG: Hippocampal-Avoidance Using Proton Therapy in Children with Brain Tumors

Phase II Study of Hippocampal-Avoidance Using Proton Therapy in Low-Grade Glioma


Brain Tumor


Phase I/II

Diseases Treated:

 Low-grade glioma

Eligibility Overview:

  • At least 6 years old and younger than 22
  • Diagnosis of low-grade glioma
  1. Brief Summary

    This study investigates the feasibility of reducing radiation doses to the hippocampi (hippocampal-avoidance) using proton therapy in pediatric patients with low-grade gliomas and explores whether hippocampal-avoidance is associated with preservation of neurocognition.  

    Low-grade gliomas are the most common brain tumors in children, and a subset of these tumors are treated definitively with focal radiation therapy. These patients often survive for many years after treatment and experience late deficits in memory. Verbal recall is an important measure of memory and is associated with other important functional outcomes, such as problem-solving, independence of every-day functioning and quality of life. Decline in memory, as measured by verbal recall, is associated with radiation dose to the hippocampi.

    In this study, all patients will be planned with hippocampus-avoidance proton therapy and neurocognitive outcomes will be collected at baseline and continue to 5 years after completion of therapy.

    Primary Objective

    • To determine the feasibility of hippocampal avoidance with proton therapy in suprasellar or midline low-grade gliomas

    Secondary Objectives

    • To estimate the 3-year event-free survival for low-grade gliomas treated with hippocampal avoidance
    • To estimate the change in California Verbal Learning Test (CLVT-SD) short-term delay from baseline to 3 years and from baseline to 5 years
    • To compare CLVT-SD and Cogstate neurocognitive scores in patients with proton therapy plans that: (1) meet first priority radiation therapy (RT) dose constraints, (2) meet second priority RT dose constraints but not first priority RT dose constraints, and (3) that did not meet either first or second RT priority dose constraints

    Eligibility Criteria

    Inclusion criteria include:

    • At least 6 years old and younger than 22 years old
    • Diagnosis of one of the following:
      • Pilocytic astrocytoma
      • Pilomyxoid astrocytoma
      • Pleomorphic xanthoastrocytoma
      • Ganglioglioma
      • Optic pathway glioma
      • Diffuse astrocytoma
      • Low-grade neuroepithelial tumor
      • Low-grade glioneuronal tumor
      • Low-grade glioma
    • Tumor located in suprasellar region or midline structures
    • No concurrent chemotherapy or targeted therapy, including but not limited to BRAF-inhibitors and MEK-inhibitors
    • Must be able to undergo contrast-enhanced brain MRI

    Exclusion Criteria include:

    • Pregnant or breastfeeding
    • Prior CNS radiation
    • Gross total resection and no measurable disease
    • Evidence of metastatic disease
    • WHO grade II midline tumor with H3K27M mutation, IDH-mutant glioma, grade II ependymoma and subependymoma, pituicytoma, spindle cell oncocytoma or granular cell tumor of the sellar region
    • Tumor that directly invades bilateral hippocampi or gross tumor volume extending into bilateral hippocampi

    Study Sites

    St. Jude Children’s Research Hospital, Memphis, Tennessee
    Collaborating sites in the U.S.

  2. About this study

    This study examines how a specific proton therapy radiation treatment affects memory and learning in young patients with low-grade glioma brain tumors. Radiation therapy is a standard treatment for low-grade gliomas. Proton therapy is a type of radiation therapy.

    In this study, the proton therapy will be designed to avoid the part of the brain called the hippocampus. The hippocampus is important for memory and thinking. Other studies have shown that memory is preserved in adult patients when radiation therapy avoids the hippocampus. There is no proof of this in children, adolescents and young adults.

    You may or may not benefit from taking part in this study. However, you may help doctors learn more about your cancer which may help children and adolescents in the future.

    Purpose of this clinical trial

    The main purpose of this study is to find out what happens, good and bad, to memory and learning when the hippocampus is avoided during proton therapy radiation.

    Eligibility Overview

    • At least 6 years old and younger than 22
    • Diagnosis of low-grade glioma
  3. HALGG  Quick View
    Sponsor St. Jude Children’s Research Hospital identifier NCT04065776
    Trial start date

    August 2019

    Estimated enrollment

    67 (including all sites)
    Study type Interventional
    Study phase Phase II
    Conditions Low-grade glioma
    Ages Between 6 and 22 years old
    Principal investigator Thomas Merchant, DO, PhD
    Study site St. Jude Children’s Research Hospital & collaborating sites outside the U.S.
    For a consultation or to discuss HALGG St. Jude Physician/Patient Referral Office

St. Jude Children’s Research Hospital
262 Danny Thomas Place
Memphis, TN 38105  USA
Voice: 1-888-226-4343 or 901-595-4055
24-Hour Emergency Access Pager: 1-800-349-4334

The above information is intended to provide only a basic description about a research protocol that may be currently active at St. Jude. The details made available here may not be the most up-to-date information on protocols used by St. Jude. To receive full details about a protocol and its status and or use at St. Jude, a physician must contact St. Jude directly.