The prognostic impact of functional imaging with 123I-mIBG in patients with stage 4 neuroblastorna >1 year of age on a high-risk treatment protocol:: Results of the German Neuroblastoma Trial NB97

Aim/Purpose: (123)I-meta-iodobenzylguanidine ((123)I-mIBG) scintigraphy is well established for staging and evaluation of response in children with high-risk neuroblastoma but its prognostic value in highly intensive first-line treatment protocols is uncertain. The presence of any (123)I-mIBG positive tumour tissue was correlated with event-free survival (EFS) and overall survival (OS). Patients and methods: The prognostic impact of residual (123)I-mIBG uptake into the primary tumour and metastases for predicting outcome in 113 stage 4 neuroblastoma patients > 1 year of the German Neuroblastoma Trial NB97 was assessed using a univariate log-rank test and multivariate Cox regression analysis. Results: All patients had (123) I-mIBG positive disease at initial staging. After four courses of induction chemotherapy, 71% of patients were still (123)I-mIBG positive for the primary tumour and 61% for metastases. After six courses, 39% of patients had (123)I-mIBG uptake by the primary tumour and 45% residual (123)I-mIBG positive metastatic disease. The (123)I- mIBC status of the primary tumour site had no bearing on outcome. Residual 123I-mIBG positive metastatic disease after four (3-y-EFS 25.7 +/- 5.3% versus 55.9 +/- 7.6%, p = 0.009; 3-y-CS 49.8 +/- 6.1% versus 65.0 +/- 7.3%; p = 0.021) and after six chemotherapy cycles (3-y-EFS 27.5 +/- 6.2% versus 47.4 +/- 6.4%, p = 0.011; 3-y-CS 50.5 +/- 7.1% vs 60.0 +/- 6.4%, p = 0.031) was associated with poor outcome. Conclusion: Functional imaging with (123)I-mIBG scintigraphy can identify poor responders with any persistent metastatic (123)I-mIBG uptake who are at a high risk of disease relapse. (123)I-mIBG response of the primary tumour site had no bearing on outcome. (C) 2008 Elsevier Ltd. All rights reserved.