We have thus suggested, by an integrated molecular and immunohistochemical diagnostic approach, that the documentation of extensive NPMc+ staining in more than 20% of cells with multilineage involvement, on BM trephine biopsies of two adult patients with presumptive morphological diagnosis of MDS/MPN but harboring NPM1 mutations, could be sufficient to eventually define a NPMc+ AML diagnosis [69], as detailed in Table 2. The gene discussed is NPM1; the disease is myelodysplastic syndrome.