Objectives: To characterize the frequency and temporal patterns of anterior segment findings after radiotherapy for sinonasal and nasopharyngeal cancer, with particular focus on anterior segment neovascularization and its association with superselective intra-arterial cisplatin infusion with concurrent radiotherapy (RADPLAT). Methods: We retrospectively reviewed 113 patients treated with intensity-modulated radiotherapy between 2019 and 2022. Anterior segment findings were evaluated using the whole cohort as the denominator and among patients referred for ocular symptoms. Cumulative incidence was estimated with death as a competing risk using the Aalen–Johansen estimator and compared using Gray’s test. Results: Median follow-up was 1666 days. Forty-seven patients (41.6%) were referred to ophthalmology. Anterior segment findings occurred in 16/60 patients (26.7%) with nasal cavity cancer and 13/31 (41.9%) with maxillary sinus cancer (p = 0.16); 5-year cumulative incidences were 27.7% and 46.1%, respectively (p = 0.018). Anterior segment neovascularization occurred in 7/113 patients (6.2%), including 6/21 (28.6%) treated with RADPLAT and 1/92 (1.1%) without RADPLAT (p < 0.001); 5-year cumulative incidences were 31.4% and 1.4%, respectively (p < 0.001). Among patients with maxillary sinus cancer, neovascularization occurred in 5/19 RADPLAT-treated patients and 0/12 non-RADPLAT patients (p = 0.13); however, median follow-up was substantially shorter in the non-RADPLAT group (385 vs. 1784 days). Neovascularization developed late (median, 975 days), and four affected patients had final best-corrected visual acuity below 0.05. Conclusions: Anterior segment findings showed distinct temporal patterns after radiotherapy. Late, vision-threatening neovascularization was strongly associated with RADPLAT, although causality cannot be established because treatment selection was confounded by tumor site, disease extent, orbital invasion, and radiotherapy characteristics. These findings identify anterior segment neovascularization as an important safety signal warranting prospective evaluation. Standardized baseline ophthalmological assessment, long-term surveillance, and patient-level ocular dosimetry are needed to clarify mechanisms and define appropriate follow-up strategies.

Diffuse intrinsic pontine glioma (DIPG) is a highly aggressive brainstem tumor with a poor prognosis, for which radiotherapy remains the only established treatment. Although reirradiation at first progression has been reported to provide symptomatic relief and survival benefit, the role of a third course of irradiation remains unclear. In this study, we report 3 cases of DIPG treated with a third course of radiotherapy at second recurrence and conduct a literature review to evaluate its clinical efficacy and safety. All 3 patients demonstrated radiologic disease stabilization following the third course of irradiation, with 1 patient showing partial neurological improvement. No permanent severe toxicity attributable to the third course of radiotherapy was observed; 2 patients transiently experienced consciousness disturbance, cerebral edema, and/or respiratory dysfunction. To further assess the clinical significance of this approach, we analyzed previously reported cases of DIPG treated with 3 courses of radiotherapy. Of the 21 identified rare cases, 13 with sufficient clinical data were included in the analysis. The median radiation doses for the first, second, and third courses were 54.0 (39.0 to 54.0), 20.0 (19.8 to 36.0), and 20.0 (12.0 to 24.0) Gy, respectively. Total median radiation doses of 3-course irradiation were 94.0 Gy (79.0 to 111.6). The median survival after the third irradiation was 5.5 (2 to 13) months, and the median overall survival was 20.5 (15 to 102) months, measured from the start of the first radiation. A radiologic response greater than stable disease was observed in 69.2% of cases, whereas clinical improvement or stabilization was noted in 93.7% of cases. Although further studies with larger cohorts are needed to clarify the efficacy and particularly the safety of this treatment due to the limited data on adverse events, 3 courses of irradiation may be a viable option for children with DIPG, with careful consideration of the risks and benefits.