Giorgio L. Porro

Background: The current standard therapy for pediatric optic pathway/hypothalamic glioma (OPHG) is systemic anticancer therapy (SAT) over surgery and radiotherapy. Nevertheless, recurrent radiological or clinical tumor progression after SAT forms a considerable challenge. Sporadic OPHGs are considered to have a higher tendency toward progression after first-line systemic anticancer therapy (SAT) compared to neurofibromatosis type-1-associated (NF1) OPHGs. Methods: The objective of this study was to conduct a national retrospective cohort analysis of children who received various treatments for a progressive OPHG, involving the hypothalamus and/or chiasm and/or optic radiations. The study aimed to examine the differences in clinical course and the range of treatment modalities applied to both sporadic and NF1-associated OPHGs between 1995 and 2020. Additionally, we sought to identify risk factors for 3- and 5-year progression following first- and second-order SAT. Results: In total, 136 children received treatment, of whom 49 of 136 (36.0%) had NF1. Within a median of 7.5 years (range: 0.1–23.8 years) of follow-up, sporadic OPHGs received more treatments compared to NF1-associated OPHGs (median of 2 (range: 1–8) vs. median of 1 (range: 1–7) (p < 0.01)). Nine children with sporadic OPHGs (6.6%) died. Of 112 children (82.4%) receiving SAT, 92% received combined first-line vincristine and carboplatin. These children had a 3- and 5-year progression-free survival of 61.8% (95% CI: 51.0–72.6%) and 48.4% (95% CI: 38.0–58.8%), respectively. Sporadic OPHGs had a higher rate of second progression (p < 0.01). Starting first-line vincristine and carboplatin at an age below one year was the only independent risk factor for progression. Conclusions: In this national historic cohort of pediatric OPHGs, four out of five children received SAT. Sporadic OPHGs received a higher number of various SATs compared to NF1-associated OPHGs, but the sporadic appearance of OPHGs was not an independent risk factor for progression after combined vincristine and carboplatin, as ‘age below one year at the start’ was the only factor.

Backgrounds: Bevacizumab (BVZ) is used as a subsequent line of treatment for pediatric optic pathway glioma (OPG) in the case of progression. Data on the treatment effect concerning tumor progression and visual function are scarce and nationwide studies are lacking. Methods: We performed a retrospective, nationwide, multicentre cohort study including all pediatric patients with OPG treated with BVZ in the Netherlands (2009–2021). Progression-free survival, change in visual acuity and visual field, MRI-based radiologic response, and toxicity were evaluated. Results: In total, 33 pediatric patients with OPG were treated with BVZ (median 12 months). Visual acuity improved in 20.5%, remained stable in 74.4%, and decreased in 5.1% of 39 of all analysed eyes. The monocular visual field improved in 73.1%, remained stable in 15.4%, and decreased in 7.7% of 25 analysed eyes. Radiologic response at the end of therapy showed a partial response in 7 patients (21.9%), minor response in 7 (21.9%), stable disease in 15 (46.9%), and progressive disease in 3 (9.3%). Progression-free survival at 18 and 36 months after the start of BVZ reduced from 70.9% to 38.0%. Toxicity (≥grade 3 CTCAE) during treatment was observed in five patients (15.2%). Conclusion: Treatment of BVZ in pediatric patients with OPG revealed stabilisation in the majority of patients, but was followed by progression at a later time point in more than 60% of patients. This profile seems relatively acceptable given the benefits of visual field improvement in more than 70% of analysed eyes and visual acuity improvement in more than 20% of eyes at the cessation of BVZ.

To this day, the most popular method of choice for testing visual field defects (VFDs) is subjective standard automated perimetry. However, a need has arisen for an objective, and less time-consuming method. Pupil perimetry (PP), which uses pupil responses to onsets of bright stimuli as indications of visual sensitivity, fulfills these requirements. It is currently unclear which PP method most accurately detects VFDs. Hence, the purpose of this study is to compare three PP methods for measuring pupil responsiveness. Unifocal (UPP), flicker (FPP), and multifocal PP (MPP) were compared by monocularly testing the inner 60 degrees of vision at 44 wedge-shaped locations. The visual field (VF) sensitivity of 18 healthy adult participants (mean age and SD 23.7 ± 3.0 years) was assessed, each under three different artificially simulated scotomas for approximately 4.5 minutes each (i.e. stimulus was not or only partially present) conditions: quadrantanopia, a 20-, and 10-degree diameter scotoma. Stimuli that were fully present on the screen evoked strongest, partially present stimuli evoked weaker, and absent stimuli evoked the weakest pupil responses in all methods. However, the pupil responses in FPP showed stronger discriminative power for present versus absent trials (median d-prime = 6.26 ± 2.49, area under the curve [AUC] = 1.0 ± 0) and MPP performed better for fully present versus partially present trials (median d-prime = 1.19 ± 0.62, AUC = 0.80 ± 0.11). We conducted the first in-depth comparison of three PP methods. Gaze-contingent FPP had best discriminative power for large (absolute) scotomas, whereas MPP performed slightly better with small (relative) scotomas.

Background: Children with a brain tumor are prone to develop visual impairment, which to date is often underestimated and unrecognized. Our aim was to assess the prevalence of ophthalmological evaluation and abnormal ophthalmological findings, and investigate whether demographic and tumor-related characteristics are associated with abnormal ophthalmological findings in children presenting with a primary brain tumor. Methods: Medical records of all 90 children diagnosed with a primary brain tumor between June 2018 and May 2019 and treated at the Princess Máxima Center for Pediatric Oncology, a tertiary referral center in the Netherlands, were retrospectively reviewed. Univariate regression analysis was used to investigate associations between demographic, tumor-related and clinical characteristics, and abnormal ophthalmological findings. Results: Sixty children (34 male [56.7%]; median [range] age, 9.3 [0–16.9] years) underwent ophthalmological evaluation within 6 weeks before or after diagnosis, 11 children (5 male [45.5%]; median [range] age, 5.7 [0.1–17.2] years) were seen more than 6 weeks before or after diagnosis, and 19 children (7 male [36.8%]; median [range] age, 7.2 [1.9–16.6] years) did not receive ophthalmological evaluation within at least 6 months from diagnosis. A total of 19 children (21.1%) presented with visual symptoms as first sign leading to the diagnosis of a brain tumor. Children who presented with visual symptoms (odds ratio [OR], 22.52; 95% confidence interval [CI], 4.90–103.60) and/or hydrocephalus (OR, 3.60; 95% CI, 1.38–9.36) at diagnosis were more often seen for ophthalmological evaluation. The most common abnormal ophthalmological findings were eye movement disorders (66.0%), papilledema (44.1%), and visual field defects (58.1%). Eye movement disorders occurred more frequently in patients with an infratentorial tumor (OR, 4.71; 95% CI, 1.03–21.65). The risk of papilledema was associated with older age (OR, 1.19; 95% CI, 1.05–1.34), hydrocephalus (OR, 9.63; 95% CI, 2.68–34.61), and infratentorial (OR, 9.11; 95% CI, 1.77–46.78) and supratentorial (OR, 13.13; 95% CI, 1.92–89.52) tumors. Conclusions: In this study, most children with a primary brain tumor underwent ophthalmological evaluation around diagnosis, 21% of the children were not evaluated. The high prevalence of abnormal ophthalmological findings stresses the importance of early standardized ophthalmological evaluation to detect visual impairment and provide timely treatment to potentially prevent permanent visual loss.