Format

Send to

Choose Destination
Int J Radiat Oncol Biol Phys. 2019 Jan 23. pii: S0360-3016(19)30162-2. doi: 10.1016/j.ijrobp.2019.01.078. [Epub ahead of print]

Outcomes Following Proton Therapy for Pediatric Low-Grade Glioma.

Author information

1
Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, FL. Electronic address: dindelicato@floridaproton.org.
2
Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, FL.
3
Department of Nemours Children's Health System, Jacksonville, FL, USA.
4
Department of Neurosurgery, University of Florida College of Medicine, Jacksonville, FL.

Abstract

BACKGROUND/OBJECTIVES:

Dosimetric studies show that proton therapy can reduce the low/intermediate radiation dose to uninvolved tissue in children with low-grade glioma (LGG). For this reason, LGG is the 4th most common pediatric tumor treated with proton therapy, yet clinical outcome data on efficacy and toxicity are limited.

DESIGN/METHODS:

We reviewed the medical records of 174 children (≤21 years old) with non-metastatic LGG enrolled on a prospective protocol and treated with proton therapy between 2007 and 2017 to assess clinical outcomes and toxicity, and analyze patient, tumor, and treatment-related variables.

RESULTS:

Median age was 10.2 years (range, 2-21). Fifty-eight percent of tumors were WHO grade I; 30% WHO grade II; 12% were diagnosed on imaging characteristics alone. The most common histology was pilocytic astrocytoma (47%). The most common tumor subsites were diencephalon/optic pathway (52%), caudal brainstem (17%), and cerebellum (13%). Forty-two percent received chemotherapy before radiotherapy. The median follow-up was 4.4 years. The 5-year actuarial rates of local control, progression-free survival, and overall survival were 85% (95% CI 78-90%), 84% (95% CI 77-89%), and 92% (95% CI 85-95%). On univariate analysis, brainstem/spinal cord tumor location (62% vs. 90% elsewhere) and dose <54 GyRBE (67% vs. 91% for 54 GyRBE) were associated with inferior local control (p <0.01 for both). Twenty-two patients (12.6%) experienced acute nausea or vomiting requiring ondansetron; 2 patients (1.1%) required corticosteroids. Serious toxicities (4% of patients) included brainstem necrosis requiring corticosteroids (n=2), symptomatic vasculopathy (n=2), radiation retinopathy (n=1), epilepsy (n=1), and death from radiation-induced high-grade glioma (n =1). Thirty-nine patients (22%) developed new-onset central hormone deficiency. Pseudoprogression was observed in 32.1%.

CONCLUSION:

Compared to modern photon series, proton therapy reduces the radiation dose to developing brain tissue, diminishing acute toxicities without compromising disease control.

KEYWORDS:

brain; low-grade glioma; optic pathway glioma; outcomes; proton therapy; radiation therapy

PMID:
30684665
DOI:
10.1016/j.ijrobp.2019.01.078
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center