No abstract

Myelodysplastic syndrome (MDS) is a diverse group of clonal hematologic neoplasms. Different medications have been tried in MDS; however, no effective treatment has been yet established. We report a patient with MDS who achieved a complete remission in response to combination therapy of danazol, retinoic acid, and prednisone. A 53-year-old female presented with pancytopenia, macrocytosis, and hypercellular bone marrow with erythroid hyperplasia and dysplasia and 10% ringed sideroblasts. Cytogenetic studies revealed the presence of two abnormal clones. She was diagnosed as having MDS-refractory anemia and was given blood transfusions to maintain blood cell counts at acceptable levels. At the same time, she was started on a combination of danazol (600 mg/day), retinoic acid (100 mg/day), and prednisone (10 mg every other day). Fourteen months later, the patient was in complete hematologic remission; she had normal peripheral blood count, and the blood smear showed normal morphology. Bone marrow studies revealed normal trilineage hematopoiesis. She was continued on the same combination treatment for 86 months, and she remained in complete clinical remission. Eighty-eight months from diagnosis, she relapsed with acute myeloid leukemia. This is the first reported case of MDS-RA that sustained a complete hematologic remission for a prolonged period in response to this combination treatment. This report indicates that restoration of normal hematopoiesis, prolongation of disease-free survival, and delay in the transformation to acute leukemia may be achieved by this combination of treatment in a subset of patients with MDS, especially refractory anemia with severe thrombocytopenia.

Acute promyelocytic leukemia (APL) is characterized by increased promyelocytes in the marrow that harbor a t(15;17) and promyelocyte leukemia (PML)/RARalpha fusion gene. The oncogenic gene product is believed to act through disruption of the transcription-modulating function of RARalpha. Differentiation of promyelocytes and remission is achieved with all transretinoic acid (ATRA) therapy usually in combination with chemotherapy. This report describes a patient with the t(15;17) who did not respond typically to ATRA and IDAC induction chemotherapy, although achieved and remains in complete remission five years following induction and one consolidation with high dose cytarabine (HIDAC). RT-PCR and sequencing revealed a novel fusion of RARalpha exon 3 to PML exon 5 that creates a frameshift and premature stop codon in the RARalpha portion of the transcript. Since none of the RARalpha functional domains are maintained, this case highlights the possibility that PML/RARalpha may directly affect promyelocyte differentiation through disruption of PML function.