MIPSS70 identifies as significant risk factors for OS both clinical factors (anemia, leukocytosis, thrombocytopenia, constitutional symptoms, and circulating blasts ≥2%) and nonclinical conditions, not included in the previous traditional models, such as bone marrow fibrosis grade ≥2, absence of CALR type-1 mutation, presence of high-molecular risk mutation (ASXL1, EZH2, SRSF2, and IDH1/2), and the number of two or more high-molecular risk mutations. This evidence concerns the gene ASXL1 and Increased total leukocyte count.