Excellent Local Control from Radiation Therapy for High-risk Neuroblastoma

Purpose: Local recurrence has been demonstrated in previous studies to be one of the obstacles to cure in neuroblastoma. Radiation therapy indications, optimal dose, and technique are still evolving. Here we report our experience of high-risk neuroblastoma patients who received local radiation therapy as part of their cancer management.

Methods And Materials: We conducted a retrospective study of 34 high-risk neuroblastoma patients who received radiation therapy to local sites of disease from March 2001 until February 2007 at our institution as part of their multimodality therapy.

Results: At a median follow-up of 33.6 months, 6 patients died of disease, 7 patients were alive with disease, and 21 patients were in clinical remission. Eleven patients relapsed, all distantly. Two patients failed locally in addition to distant sites. Both of these patients had persistent gross disease after induction chemotherapy and surgery. Our 3-year local control, event-free survival, overall survival were 94%, 66%, and 86%, respectively.

Conclusion: Patients with high-risk neuroblastoma in our series achieved excellent local control. Doses of 21-24 Gy to the primary tumor site appear to be adequate for local control for patients in the setting of minimal residual disease after induction chemotherapy and surgery. Patients with significant residual disease may benefit from radiation dose escalation, and this should be evaluated in a prospective clinical trial.