We evaluated the presence of circulating BDCA1+CD14+ cells in patients with acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphatic leukemia (ALL), chronic lymphatic leukemia (CLL), biphenotypical acute leukemia (B- and T-ALL), and idiopathic myelofibrosis (IMF, rise of CD34+ hematopoietic stem cells) (Figure 1; methods in Appendix A). This evidence concerns the gene CD34 and acute lymphoblastic leukemia.