Effect of Proton Therapy on Long-term Clinical and Neurocognitive Outcomes for Pediatric Brain Tumors

Brain tumors account for approximately 20 percent of all pediatric tumors. Treatment generally involves surgery, chemotherapy and/or radiation therapy.

Photon-based radiotherapy, which is used in most pediatric treatment centers to treat brain tumors, can be associated with significant toxicity on the developing brains of infants and young children, and profound late-effects on survivors. These include vision and hearing loss, endocrine problems and neurocognitive deficits. These toxicities and side effects result from the destructive effects of conventional photon therapy scattered on surrounding normal brain tissue.

In contrast with photon radiotherapy, proton therapy, an emerging radiotherapy, is a more precise radiotherapy modality and offers greater normal tissue sparing.

We believe the precision of proton therapy will result in reduced toxicities and side effects and we hypothesize (this hasn’t been proven yet) improved long-term neurocognitive outcomes for children with brain tumors.

However, because of the “newness” of proton therapy, the long-term effects of proton therapy on neurocognitive development in infants and young children has not been well studied.

Researchers at the Center for Childhood Cancer Research, including Jane E. Minturn, MD, PhD, Christine E. Hill-Kayser MD, and Iris Paltin, PhD, are evaluating the effects of proton therapy and long-term clinical and neurocognitive outcomes on infants and young children with a variety of pediatric brain cancers, including medulloblastoma, atypical teratoid rhabdoid tumor, low-grade glioma and other tumors.

Early results from these clinical studies reveal that proton therapy is well-tolerated by very young children with minimal acute toxicity and excellent disease control. Additional long-term follow up studies are currently underway to assess the longer term clinical and neurocognitive effects (greater than three years) of proton therapy on children with brain tumors.