Clonal disease of the hematopoietic stem cell, defined by persistent monocytosis (at least 3 months).
Approximately 40% of cases show a RAS gene mutation, are BRC-ABL1 negative, and the PDGFRA and PDGFRB transformations are absent.
Chronic myelomonocytic leukemia: Chronic myelomonocytic leukemia, bone marrow, HE 100x (72740) Chronic myelomonocytic leukemia, bone marrow, PAS 100x (72737)