HIF1A and myeloid sarcoma: Hypoxia-like tissue alterations, predominantly characterized by the accumulation of the hypoxia-inducible factor-1α (HIF-1α), occur at a very early stage in MS pathogenesis (Aboul-Enein et al., 2003; Graumann et al., 2003; Lassmann, 2003; Stadelmann et al., 2005; Marik et al., 2007; Zeis et al., 2008).