t(1;7;22)(p13;q21;q13) is a novel 3‑way variant of t(1;22)(p13;q13) neonatal acute megakaryoblastic leukemia: A case report

• DOI: 10.3892/mco.2023.2614
• Publication Date: 2023-01-31T13:31:24Z
• Authors: Julie Messiaen; Anne Uyttebroeck; Lucienne Michaux; Peter Vandenberghe; Nancy Boeckx; Sandra Jacobs
• Keywords: chromosomal translocation; pediatric hematology; 03 medical and health sciences; 0302 clinical medicine; Case Report; acute myeloid leukemia; 3. Good health

Acute megakaryoblastic leukemia (AMKL) is a rare disease, occurring mostly in infants and young children. The chromosomal translocation t(1;22)(p13;q13), resulting in the RBM15-MKL1 fusion gene, is a recurrent and diagnostic translocation in infants with AMKL. The present case report describes a case of a newborn girl, without Down's syndrome, with congenital AMKL. At birth, the infant had hepatosplenomegaly and the peripheral blood count revealed anemia, thrombopenia and leukocytosis, with 28% blasts. Immunophenotyping demonstrated blasts positive for CD34, CD61 and CD42b. Karyotyping of these blasts (R-banding) showed a hitherto unreported chromosomal translocation, t(1;7;22)(p13;q21;q13), a 3-way variant of the t(1;22)(p13;q13) variant. Fluorescent in situ hybridization analysis confirmed the presence of the RBM15-MKL1 fusion gene.