<P> Myeloid neoplasms always concern bone marrow cell lineage and are related to hematopoietic cells . Myeloid tissue can also be present in the liver and spleen in fetuses, and sometimes even in adults as well, which leads to extramedullary hematopoiesis . </P> <P> There is one other sense of myeloid that means "pertaining to the spinal cord", but it is much less commonly used . Myeloid should not be confused with myelin, referring to an insulating layer covering the axons of many neurons . </P>

What type of leukocytes are not derived from myeloid stem cells