Reirradiation of Pediatric Tumors Using Hypofractionated Stereotactic Radiotherapy

Background: This study aimed to evaluate the efficacy and safety of hypofractionated stereotactic radiotherapy for reirradiation of recurrent pediatric tumors. Methods and Materials: The study included 23 pediatric patients who were reirradiated using hypofractionated stereotactic radiotherapy in the radiation oncology department between January 2008 and November 2013. In total, 33 tumors were treated—27 (82%) cranial and 6 (18%) extracranial. Hypofractionated stereotactic radiotherapy was administered due to recurrent disease in 31 (94%) tumors and residual disease in 2 (6%) tumors. The median total dose was 25 Gy (range: 15-40 Gy), and the median follow-up was 20 months (range: 2-68 months). Results: The 1-year and 2-year local control rates in the entire study population were 42% and 31%, respectively. The median local control time was 11 months (range: 0-54 months) following hypofractionated stereotactic radiotherapy. The patients with tumor response after hypofractionated stereotactic radiotherapy had significantly longer local control than the patients with post-hypofractionated stereotactic radiotherapy tumor progression (21 vs 3 months, P <.001). Tumor volume <1.58 cm³ was correlated (not significantly) with better local control (23 vs 7 months, P =.064). Conclusion: Reirradiation of pediatric tumors using hypofractionated stereotactic radiotherapy is a safe and effective therapeutic approach. This treatment modality should be considered as a treatment option in selected pediatric patients.