The faculty agreed that a thorough histomorphological and immunohistochemical (or flow cytometric) investigation of BM cells is essential for the diagnosis of CMML (recommended marker: CD14)[43] and delineation between CMML-1 and CMML-2 (recommended marker: CD34), which may be difficult as monoblasts or promonocytes often lack CD34 [41,42]. This evidence concerns the gene CD34 and chronic myelomonocytic leukemia.