Abstract Objectives To evaluate outcomes of paediatric high-grade glioma (HGG) and diffuse midline glioma (DMG), including classic diffuse intrinsic pontine glioma (DIPG), before and after establishment of Hong Kong Children’s Hospital in 2019, and to assess the impact of molecular diagnostics, targeted therapy, and surgical extent. Methods This is a territory-wide retrospective review on 145 patients (68 HGG; 77 DMG including DIPG) diagnosed from 1999–2025 in Hong Kong. Patients were stratified by diagnostic era: pre2019 (HGG n = 51; DMG n = 27) and post-2019 (HGG n = 17; DMG n = 50). Overall survival (OS), and its association with use of molecular testing, and targeted therapy were analysed. For HGG, association between extent of resection and OS was also examined. Results In HGG, median OS improved from 1.06 years (range: 0.02–21.44) before 2019 to 1.82 years (range: 0.01–6.51) after 2019 (log-rank p= 0.02). Use of molecular diagnostics rose from 18% (n = 9/51) to 100% (n = 17/17). Targeted therapy was given to 4% (n = 2/51) of pre-2019 cases versus 65% (n = 11/17) of post-2019 cases; treated patients had a longer median OS (1.88 vs 1.06 years; log-rank p= 0.007). Infant subtypes, including infant glioblastoma and infant-type hemispheric glioma (n = 7), showed favourable outcomes, with 71% (5/7) being long-term survivors. Two patients on molecularly-matched therapies (BRAF V600E–mutant gliosarcoma with acquired PIK3CA mutation, and PDGFRA-amplified glioblastoma) achieved exceptional survivals of 5.6 and 3.8 years, respectively. The extent of surgical resection, however, did not correlate with OS. In DMG, OS remained poor: 0.70 years (range: 0.15–1.92) before 2019 versus 0.67 years (range: 0.01–3.46) after 2019. Targeted agents were used in 9/27 (33%) before 2019 and 12/50 (24%) after 2019, yet even biomarker-selected targeted therapy guided by molecular diagnostics in the post-2019 cohort did not confer any survival advantage. Conclusion Survival for paediatric HGG has improved with the integration of molecular diagnostics and biomarker-driven targeted therapy. Nevertheless, outcomes for DMG remain dismal despite increased molecular testing and targeted approaches, underscoring the need for more effective strategies.
Mak et al. (Tue,) studied this question.