dditonal file 1: Clinical and biological characteristics of 90 NT specimens included in the study. INSS = International Neuroblastoma Staging System; Diagnosis: NB = neuroblastoma, GNB = ganglioneuroblastoma, GN = ganglioneuroma; Disease status: A = alive, D = dead; EFS = Event free survival; qRT-PCR = Quantitative real-time PCR; IHC = immunohistochemistry; n.a = not available data Immunohistochemical analysis of CHD5 expression in NTs Results are displayed as percentage of CHD5 immunopositive cells present in each tumor specimen. Staining intensity: 0 = negative; 1 = weak staining; 2 = strong staining, 3 = very intense staining. Proportion of positive cells values (<25% = 1; 25-75 = 2; >75% = 3). Intensity and positive cell values were multiplied together to provide a single score for each case.