Jurnal Internasional Campuran-fenotipe leukemia akut, T / megakaryoblastic | Jurnal Darah
A newborn boy is presented with leukocytosis (45 × 10 9 / L), anemia (10 g / dL), and thrombocytopenia (12 × 10 9 / L). Peripheral blood flow cytometry shows CD45 dim-to-negative (panel A) explosions positive for CD13, CD33 (subset), CD117, CD34, CD42b (panel B;> 50% CD34-positive explosions expressing CD42b), CD41, and cyCD3 ( panel C), while negative for CD1a, CD2, sCD3, CD4, CD5, CD7, CD8, CD19, and cyMPO. Bone marrow examination identified populations of dimorphic explosions (28%) with megakaryoblasts and lymphoblast features (panel D; aspirate smear, Wright-Giemsa staining, original magnification × 1000) and fibrosis (panel E; core biopsy, hematoxylin and eosin staining, original enlargement) × 600). An immunohistochemical double stain for GATA1 (brown) and CD3 (magenta) shows many biphenotypic explosions with megakaryocytic / T-lymphoid differentiation (panel F; original magnification × 600, inset × 1000). Conventional cytogenetic karyotypes are 46, XY. Generation of sequencing identifies new fusion CBFA2T3-GLIS3 . He underwent acute induction of lymphoblastic leukemia and allogeneic stem cell transplantation but relapsed with acute acute megakaryoblastic leukemia (cyCD3 negative), which was refractory for further treatment.
Acute leukemia mixed, T / megakaryoblastic phenotype, very rare. The cases presented here meet the criteria for both T-lineage assignments (cyCD3 intensity achieving normal T-lymphocytes) and acute megakaryoblastic leukemia (≥1 megakaryocytic markers in> 50% blasts) and thus represent one of the first documented examples of this. unusual entity.