Second, neuroblastic tumor cells, along with inflammatory mediators such as IL-6, IL-8 and TGF-β1 (30) produced by bone marrow stromal cells (BMSC) stimulated by these cells, can interfere with the normal process of red blood cell production, leading to increased variability in red blood cell size and ultimately resulting in an elevated RDW-CV value (18). This evidence concerns the gene IL6 and neoplasm.