Late relapse and prognosis for neuroblastoma patients surviving 5 years or more: a report from the European Neuroblastoma Study Group "Survey"

BACKGROUND AND PROCEDURE: Most deaths from neuroblastoma occur within 2 years of diagnosis but there have been several anecdotal reports of relapse and death after much longer periods of follow up. In order to investigate and quantify the risk of late events we analysed data for patients registered with the European Neuroblastoma Study Group between 1982 and 1990. Out of a total of 1,277 children registered, 427 were alive with follow-up beyond 5 years from diagnosis (median follow-up of 8.8 years, range 5-14 years). Of these 406 were in remission with no prior recurrence, 16 were in remission having experienced a relapse prior to 5 years, and 5 were alive with progressive disease. RESULTS: For the 406 patients in remission with no prior relapse the 10 year progression free survival (PFS) was 96% (CI 94-98). For those aged over 1 year with stage 4 disease at diagnosis 10 year PFS was 88% (CI 79-96) compared to 98% (CI 97-99) for other patients combined, P< 0.001. In a multivariate analysis of all 422 patients in remission at 5 years, significant risk factors for subsequent relapse were age > 1 yr with stage 4 disease at diagnosis (relative risk 10.5, P < 0.001) and prior relapse (RR 4.2, P= 0.01). CONCLUSIONS: The results of this study emphasise the importance of longterm follow-up of patients and the need for late monitoring of clinical trials in children with neuroblastoma. They also provide a baseline for comparison with future and hopefully more effective treatment programmes.