Wide-field pulsed reduced dose rate radiotherapy (PRDR) for recurrent ependymoma in pediatric and young adult patients.

AIM: This retrospective analysis evaluates feasibility of wide-field re-irradiation using pulsed reduced dose rate (PRDR) technique in patients with recurrent ependymoma. PRDR employs a dose rate of 6 cGy/min, as opposed to 400-600 cGy/min for conventional radiation, allowing for enhanced normal tissue repair.

PATIENTS AND

METHODS

Five patients with recurrent ependymoma having eight lesions (two brain, six spinal cord) were treated with PRDR. Progression-free survival (PFS) and overall survival (OS) were estimated by Kaplan Meier method.

RESULTS

The median interval between two radiation courses was 58 months (range: 32-212 months). The median PRDR dose was 40 Gy (range: 30.6-54 Gy) with a median cumulative lifetime dose of 105.2 Gy (range: 90-162.4 Gy). At a median post-PRDR follow-up of 64 months, estimated 4-year OS and PFS from PRDR was 60% and 35.7%, respectively. None of the patients developed necrosis on serial magnetic resonance imaging scans, and only one patient had progressive mild radiculopathy.

CONCLUSION

In patients with large-volume recurrent ependymoma, re-irradiation with wide-field PRDR is a feasible option.