Experience of the Izmir Pediatric Oncology Group on Neuroblastoma: IPOG-NBL-92 Protocol

This multicentric study aimed to bring neuroblastoma patients together under IPOG-NBL-92 protocol and evaluate the results within the period between 1992 and 2001 in Izmir. Sixty-seven neuroblastoma patients from 4 pediatric oncology centers in Izmir were included in the study. IPOG-NBL-92 protocol modified from German Pediatric Oncology (GPO)-NB-90 protocol was applied: Patients in stage 1 received only surgery, while surgery plus 4 chemotherapy courses (cisplatin, vincristine, ifosfamide) were given in stage 2 and surgery plus 6 chemotherapy courses (cisplatin, vincristine, ifosfamide, epirubicin, cyclophosphamide) were given in stages 3 and 4 patients. In patients who were kept in complete remission (CR), a maintenance therapy of one year was applied. Radiotherapy was given to the primary site following induction chemotherapy plus surgery in stages 3 and 4 patients with partial remission (PR). The stages of the patients were as follows: 5% in stage 1, 39% in stage 3, 49% in stage 4, and 7% in stage 4S. Primary tumor site was abdomen in 88% of cases. CR rates were as 100% in stage 1, 76% in stage 3, 35% in stage 4, and 75% in stage 4S. Relapse was observed in 32% of patients in a median of 19 months. The median follow-up time for survivors was 33 (17-102) months. Five-year OS rate was 31% and the EFS rate was 30% in all patients. Five-year overall and event-free survival rates were 63 and 30% in stage 3, but 6 and 5%, respectively, in stage 4 patients. Univariate analysis established that the age, stage, primary tumor site, and high LDH and NSE levels conferred a significant difference. The IPOG-NBL-92 protocol has proved to be satisfactory with tolerable toxicity and reasonable CR and survival rates. However, more effective treatments suitable to Turkey's social and economic conditions are urgently needed for children over 1 year of age with advanced neuroblastoma.