Figure 6
A proposed model for the age dependence of unfavorable neuroblastoma. The model builds on the assumption of an early common cellular origin of all neuroblastomas. Depending on genetic subtype the respective tumorigenic hits differ in type, number and degree of malignant effect - most evident when comparing MNA and 11q- tumors. As tumors with alternative amplifications, putative low-to-high-risk progression, and adolescent presentation are poorly represented in the present study and in the literature these routes for tumor development are largely speculative, indicated by question marks. Abbreviation: NB: neuroblastoma; Symbols: Arrows: tumorigenic hits; Darkness of arrow: degree of malignant transformation; Arrow width/size of symbol for clinical disease: relative frequency of tumor subtype; Solid curved blue line: low-risk neuroblastoma development.