RESUMO
Secondary acute myelocytic leukemia (AML) and myelodysplastic syndromes (MDS) are known to develop in patients previously treated with different chemotherapeutic regimens. Nonrandom chromosomal abnormalities have been demonstrated in these therapy-related myeloid disorders which often evolve into refractory AML. The prognosis of these patients with conventional chemotherapy has been dismal and only allogeneic bone marrow transplantation offers a potential cure. We describe two patients who developed MDS after chemo/radiotherapy and had a spontaneous recovery. One patient was treated with MOPP-ABVD hybrid therapy for Hodgkin's disease, developed pancytopenia, marrow hypoplasia and dyserythropoiesis associated with monosomy 7. The other was treated with a combination of chemotherapy including VP-16 for Ewing's sarcoma, developed thrombocytopenia, marrow hypoplasia and dyserythropoiesis associated with an 11q23 translocation. Both patients received rhG-CSF after their cycles of chemotherapy and were considered for a bone marrow transplant. Marrow aspirates at frequent intervals showed gradual disappearance of the abnormal clone with parallel normalization of the peripheral count. In both patients G-CSF might have played a role in the development of the abnormal clone. We suggest that patients with therapy-related MDS without excess of blasts could be closely monitored for karyotypic and hematological improvement rather than transplanted immediately.