Clinical significance of intensive surgery with intraoperative radiation for advanced neuroblastoma: Does it really make sense?

Purpose: The aim of this study was to evaluate the significance of intensive surgery combined with intraoperative radiation therapy (IORT) in advanced neuroblastoma. Methods: Clinical features and outcome were reviewed in 33 advanced neuroblastoma patients (24 with INSS stage 4, 9 with stage 3), who had surgery (total excision 29, subtotal excision 4) with IORT (10 to 15 Gy) against the primary tumor site. Results:Three patients (8.8%) had relapse at the primary site, all of which arose from the unirradiated area after stem cell transplantation. Among 29 patients with total excision, disease-free survival was obtained in 15 (51.7%) for an average of 6.9 years, which included 5 survivors of 9 patients (55.9%) with amplified N-myc. In contrast, none of 4 patients with macroscopic residual survived. The Kaplan-Meier analysis showed significantly longer survival rates in the patients with total resection compared with those with macroscopic remnants. Conclusions: The intensive surgery with IORT dramatically increased the local eradication and improved the outcome even in advanced neuroblastoma with N-myc amplification. However, long-term survival was not obtained in patients with unresectable residual disease. These results may indicate the key role of surgical eradication in advanced neuroblastoma.