Long-term outcomes of the GPOH NB97 trial for children with high-risk neuroblastoma comparing high-dose chemotherapy with autologous stem cell transplantation and oral chemotherapy as consolidation

Background: This study was done to investigate the long-term event free and overall survival of high-dose chemotherapy followed by autologous stem cell transplantation (ASCT), compared to maintenance chemotherapy (MT). Patterns of recurrences and late sequelae of both arms were analysed. Methods: A randomised open label trial was conducted nationwide during 1997–2004 in Germany and Switzerland. 295 patients with high-risk neuroblastoma were randomly assigned to high-dose chemotherapy with autologous stem cell transplantation (ASCT) or maintenance chemotherapy (MT) for consolidation. Analyses were done by intention-to-treat (ITT: ASCT/MT N = 149/146), as treated (AT: N = 110/102), and treated as randomised (TAR: N = 75/70). Results: The event free survival was superior for the patients receiving ASCT compared to patients treated with MT in all three cohorts (hazard ratio [HR] for ITT 1.39, 95% confidence interval (CI) 1.05-1.85, P = 0.022, HR for AT 1.75, CI 1.24-2.47, P = 0.001; HR for TAR 2.07, CI 1.36-3.16, P = 0.001). Overall survival was also in favour of the ASCT groups (ITT: P = 0.075; AT: P = 0.017; TAR: P = 0.005). The frequencies of late sequelae were not different except for focal nodular hyperplasia of the liver observed more frequently in the ASCT arm. Conclusions: High-dose chemotherapy with autologous stem cell transplantation had a better long-term outcome compared to maintenance chemotherapy.