Reirradiation and Re-reirradiation of Pediatric Midline Gliomas

Abstract

Objectives

Children with midline gliomas have a dismal prognosis and current treatment options cannot offer cure. At progression after primary radiotherapy, reirradiation can be offered to relieve symptoms. The aim of this study is to evaluate the outcome of children treated with reirradiation for midline glioma since implementing national guidelines in 2019.

Methods

All children reirradiated for midline gliomas 2019-2023 in Sweden were retrospectively analysed. A review of medical records and treatment plans was performed to collect data on clinical and treatment characteristics, severe side effects, treatment effect and survival.

Results

Eleven patients were analysed and the median age at start of first reirradiation was 9 years (4-18). The median overall survival from end of first reirradiation was 5.6 months. The median follow-up was 4 months (0-14). The most common (91%) treatment at primary irradiation was 54 Gy in 30 fractions and at first (82%) and second (75%) reirradiation it was 20 Gy in 10 fractions. The median time between first and second irradiation was 8 months (4-27) and 6 months (6-7) between second and third irradiation. The median D2% to the brainstem was 74 Gy (59-91) at first reirradiation (n=11) and 95 Gy (77-95) at second reirradiation (n=4). In patients where the indication for reirradiation was progression of symptoms, 6 patients (67%) had relief of symptoms after reirradiation, and 3 patients (75%) had relief of symptoms after re-reirradiation. No patients had grade ≥3 side effects at reirradiation. One patient had acute respiratory grade ≥3 side effect (hyperventilation) at second reirradiation but recovered after treatment with steroids.

Conclusion

The implementation of national guidelines has harmonised how paediatric midline glioma are treated with reirradiation in Sweden. A structured follow-up shows that severe side effects are rare, and that reirradiation can offer relief of symptoms for selected patients.