Peripheral blood and bone marrow changes after treatment with ATRA and G-CSF in AML, APL and blast crisis following Vaquez's disease.

The aim of the present study was to better understand the possibility of utilizing growth factors of the myelomonocytic line in acute leukemias. The study is an examination of morphological changes and marker behavior in peripheral and bone marrow cells in AML and APL during treatment both with all-transretinoic acid (ATRA) alone and in association with chemotherapy and G-CSF. The same treatment was carried out in a patient who had been diagnosed with Vaquez's disease 15 years earlier and currently presented a bone marrow and peripheral picture of AML (80% myeloblasts) with thrombocytopenia. We observed that treatment with ATRA, alone or in association with chemotherapy, was followed by a remission of AML and especially of APL, with amelioration of the general condition of the patients. The addition of G-CSF to ATRA at the end of chemotherapy, during consequent pancytopenia, produced a rapid increase in mature peripheral granulocytes and an apparent medullary complete remission, which was more prolonged in APL than in AML; there was no increase in peripheral blasts. Discontinuation of G-CSF was followed by a relapse in the patient with AML. A patient with Vaquez's disease, in remission for 15 years and presenting a progressive increase in bone marrow and peripheral myeloblasts, did not have a positive response to the administration of ATRA; however, the association of G-CSF to ATRA was followed by a complete remission. The morphological changes observed in bone marrow and peripheral granulocytes (with changes in the main cellular markers: CD11b, CD13, CD14, CD15, CD34) seemed to express progressive modification of the single elements towards differentiation, with progressive bone marrow reduction and peripheral disappearance of blasts. The data agree with the changes observed in in vitro blasts cultured in the presence of ATRA and G-CSF.