IL6 and neuroblastoma: The analysis of prognostic factors and predictive factors revealed that the GG genotype of the rs1800795 IL-6 polymorphism was significantly associated (p < 0.001) with the high-risk category, as well as with International Neuroblastoma Staging System (INSS) stage E4 (p < 0.001) and stage M according to International Neuroblastoma Risk Group (INRG) (p < 0.001).