Assuntos
Anemia/diagnóstico , Obstrução Intestinal/diagnóstico , Intestino Delgado/patologia , Endoscopia Gastrointestinal , Feminino , Humanos , Intestino Delgado/diagnóstico por imagem , Neoplasias do Jejuno/diagnóstico , Neoplasias do Jejuno/secundário , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Melanoma/diagnóstico , Melanoma/secundário , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND AND OBJECTIVES: Clonal hematopoiesis is the hallmark of myelodysplastic syndromes, but the role played by pluripotent stem cells and progenitor cells in these disorders remains unclear. DESIGN AND METHODS: Eight female patients with myelodysplastic syndrome were studied. X-chromosome inactivation patterns were analyzed in peripheral blood granulocytes, T-lymphocytes, single colonies originating from bone marrow progenitors and pluripotent stem cells, using the human androgen receptor locus polymorphism assay. RESULTS: Granulocytes and progenitor cells were monoclonal in 7/8 cases. Immature stem cells showed a non-clonal pattern of X-inactivation and were detectable at diagnosis in the presence of clonal hematopoiesis. T-lymphocyte clonality was heterogeneous. INTERPRETATION AND CONCLUSIONS: In myelodysplastic syndromes, hematopoiesis may be dominated by a neoplastic clone by virtue of its biological advantage over a residual polyclonal, probably still normal, population of immature stem cells still able to grow in vitro.