Intraoperative radiation therapy for high-risk pediatric neuroblastoma

Purpose: To evaluate the efficacy of intraoperative radiation therapy (IORT ) in the treatment of high-risk pediatric neuroblastoma. Methods and Materials: Between 1986 and 1998, 23 children received IORT for pediatric neuroblastoma, Electron beam energies ranged from 4 MeV to 16 Me V and median dose was 10 Gy (7-16 Gy). Results: Twenty-one of 23 patients were classified as high-risk. A gross to tal resection (GTR) was achieved in 18 patients, of whom 6 experienced dise ase recurrence, 2 of which included a locoregional relapse as a component o f failure. Fourteen of 18 patients receiving IORT after a GTR are disease-f ree survivors. A second subset of 5 patients had a subtotal resection (STR) , with gross residual disease remaining after surgery. All 5 patients recur red locally, and all died of their disease. IORT was extremely well-tolerat ed in our cohort. Surgical resection and IORT resulted in the narrowing of the abdominal aorta and an atrophic kidney in 1 patient. Conclusions: For high-risk neuroblastoma patients, IORT as the only radioth erapy to the primary, produced excellent local control after a GTR, However , IORT as the sole radiotherapy to the primary was inadequate for patients with extensive adenopathy or an STR, In this setting, we are exploring the use of IORT as a boost in conjunction with external beam radiation therapy, (C) 2000 Elsevier Science Inc.