Myelotoxicity due to chemotherapy remains important due to its high incidence. It's one of the main toxicities due to medical treatments in oncology. Most regimens continue to be dose limited by this type of toxicity. It may concern red blood cells (anemia), white blood cells (leucopenia and neutropenia) and platelets (thrombocytopenia). The development of hematologic growth factors allows for new approaches and some modifications in the treatment of myelotoxicity.