Long-term visual acuity outcomes after radiation therapy for sporadic optic pathway glioma
Children with sporadic optic pathway glioma (OPG) commonly experience a decline in visual acuity (VA). This study aimed to quantify long-term VA outcomes after definitive radiation therapy (RT).
From 1997 to 2017, 41 patients underwent RT for OPG and had baseline VA testing. All patients underwent serial VA testing every 3–6 months during the first 5 years and annually thereafter. The cumulative incidence of VA decline or improvement (per eye) was estimated using death as a competing risk.
Mean follow-up was 5 years. Most tumors (93%) involved the postchiasmatic optic tracts and/or hypothalamus. Of the tumors tested for BRAF alterations (n = 15), 67% had a BRAF fusion. Median time to VA decline was 20 months in the eye with worse vision and 22 months in the better eye. For the worse eye, the 5-year cumulative incidences of VA decline and improvement were 17.9% [95% confidence interval (CI) 7–32.8%] and 13.5% (95% CI 4.7–26.7%), respectively. For the better eye, the 5-year cumulative incidences of VA decline and improvement were 11.5% (95% CI 3.5–30.7%) and 10.6% (95% CI 2.6–25.2%), respectively. Visual outcomes did not correlate with radiographic evidence of tumor progression.
The 5-year cumulative incidence of VA decline was low. VA decline is most likely to occur within the first 2 years after RT and is not associated with radiographic progression of disease, highlighting the need for frequent ophthalmologic exams during this period.
KeywordsOptic glioma Visual acuity Radiation BRAF
The authors thank Keith A. Laycock, PhD, ELS, for scientific editing of the manuscript and Tina D. Davis MBA, RHIA, Erin Kelly, MSW, and Samantha Buhler, CCRP, for assistance in data collection.
All authors receive research support from the American Lebanese Syrian Associated Charities (ALSAC).
Compliance with ethical standards
Conflict of interest
No conflicts of interest.
- 2.Pizzo PA, Poplack DG (eds) (2016) Principles and practice of pediatric oncology, 7th edn. Wolters Kluwer, PhiladelphiaGoogle Scholar
- 6.Falzon K, Drimtzias E, Picton S, Simmons I (2018) Visual outcomes after chemotherapy for optic pathway glioma in children with and without neurofibromatosis type 1: results of the International Society of Paediatric Oncology (SIOP) Low-Grade Glioma 2004 trial UK cohort. Br J Ophthalmol 102(10):1367–1371. https://doi.org/10.1136/bjophthalmol-2017-311305 CrossRefPubMedGoogle Scholar
- 13.Merchant TE, Conklin HM, Wu S, Lustig RH, Xiong X (2009) Late effects of conformal radiation therapy for pediatric patients with low-grade glioma: prospective evaluation of cognitive, endocrine, and hearing deficits. J Clin Oncol 27(22):3691–3697. https://doi.org/10.1200/JCO.2008.21.2738 CrossRefPubMedPubMedCentralGoogle Scholar
- 16.Dodge HW, Love JG, Craig WM et al (1958) Gliomas of the optic nerves. AMA Arch Neurol Psychiatry 79(6):607–621. https://doi.org/10.1001/archneurpsyc.1958.02340060003001 CrossRefPubMedGoogle Scholar
- 17.Liu GT, Volpe NJ, Galetta SL (eds) (2010) Neuro-ophthalmology: diagnosis and management, 2nd edn. Saunders, PhiladelphiaGoogle Scholar
- 22.Qaddoumi I, Orisme W, Wen J et al (2016) Genetic alterations in uncommon low-grade neuroepithelial tumors: BRAF, FGFR1, and MYB mutations occur at high frequency and align with morphology. Acta Neuropathol 131(6):833–845. https://doi.org/10.1007/s00401-016-1539-z CrossRefPubMedPubMedCentralGoogle Scholar
- 24.World Health Organization (2006) List of Official ICD-10 Updates Ratified, October 2006. Geneva. https://www.who.int/classifications/icd/2006Updates.pdf. Accessed 17 May 2019
- 27.Fangusaro J, Onar-Thomas A, Poussaint TY et al (2019) Selumetinib in paediatric patients with BRAF-aberrant or neurofibromatosis type 1-associated recurrent, refractory, or progressive low-grade glioma: a multicentre, phase 2 trial. Lancet Oncol. https://doi.org/10.1016/S1470-2045(19)30277-3 CrossRefPubMedGoogle Scholar
- 30.Fisher MJ, Avery RA, Allen JC et al (2013) Functional outcome measures for NF1-associated optic pathway glioma clinical trials. Neurology 81(21 Suppl 1):S15–S24. https://doi.org/10.1212/01.wnl.0000435745.95155.b8 CrossRefPubMedPubMedCentralGoogle Scholar