High-risk neuroblastoma in Ontario: a report of experience from 1989 to 1995.

Purpose: We did a population-based study of children with high-risk neuroblastoma to determine their survival and look for factors that had an impact on survival.

Methods: We carried out a retrospective cohort study of patients diagnosed in Ontario from 1989 to 1995. 162 cases of neuroblastoma were diagnosed in the province with 70 (43%) considered high-risk: all were older than one year of age, with 15 patients classified as International Neuroblastoma Staging System (INSS) stage 3, and 55 INSS stage 4.

Results: Stage 3 patients did significantly better than Stage 4 patients with a 5-year overall survival of 67.7% and 22.7% respectively (P = 0.015). In stage 4 patients achieving at least a partial response to up-front therapy and surviving for at least 9.5 months after diagnosis (the median time to transplant), there was no difference in survival between the 19 transplant patients and the 17 treated with chemotherapy alone (P = 0.75). However, patients transplanted by peripheral stem cell (PSC) collection did significantly better than both the bone marrow transplantation (P = 0.002) and chemotherapy-alone group (P = 0.047). There was a significant difference in up-front chemotherapy and use of radiation in the three groups (P < 0.001 and P = 0.01 respectively), but no difference in the incidence of bone and bone marrow metastases, MYCN amplification or unfavorable histology.

Conclusions: In this nonrandomized study, we found that stage 4 neuroblastoma patients alive more than 9.5 months after diagnosis, with at least a partial response to initial therapy, did significantly better with PSC transplant compared with bone marrow transplantation or chemotherapy alone.