title: Myelodysplastic syndrome without ring sideroblasts and with Janus kinase 2 gene mutation: An unusual case report.
abstract: Myelodysplastic syndrome (MDS) cases comprise a heterogeneous group of hematological disorders that are characterized by impaired hematopoiesis, with cytopenias of different grades and risk of developing acute myeloid leukemia. MDS may rarely be associated with thrombocytosis. In such cases, myelodysplasia and myeloproliferative disorders may overlap, making correct diagnosis difficult. We herein describe a case of MDS with thrombocytosis, Janus kinase 2 gene mutation-positive and Perls' staining-negative, which was initially classified as essential thrombocythemia (ET). This case highlights that MDS may be misdiagnosed as ET and inappropriate treatment may be initiated. Therefore, it is crucial to carefully combine all available data on morphology and immunophenotyping, and to perform the necessary molecular, cytogenetic and molecular cytogenetic analyses, in order to correctly diagnose this disease.
authors: Department of Pathology, Laboratory of Circulating Markers, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil; Graduation Course in Medical Sciences, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil.
authors: Maria Helena
authors: MH
authors: Ornellas
authors: Department of Pathology, Laboratory of Circulating Markers, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil.
authors: Monique
authors: M
authors: De França Silva
authors: Department of Haematology, Pedro Ernesto University Hospital (HUPE), Rio de Janeiro State University (UERJ), Rio de Janeiro 20551-120, Brazil.
authors: Cristiana
authors: C
authors: Solza
authors: Department of Haematology, Pedro Ernesto University Hospital (HUPE), Rio de Janeiro State University (UERJ), Rio de Janeiro 20551-120, Brazil.
authors: Stella Beatriz Sampaio
authors: SB
authors: De Lucena Gonçalves
authors: Department of Pathology, Laboratory of Circulating Markers, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil; Graduation Course in Medical Sciences, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil.
authors: Liliane
authors: L
authors: Silva De Almeida
authors: Laboratory of Pathology, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 21040-360, Brazil.
authors: Jackline
authors: J
authors: De Paula Ayres-Silva
authors: Cytogenetics Laboratory, Faculty of Medical Sciences, Rio de Janeiro State University (UERJ), Rio de Janeiro 20551-120, Brazil.
authors: Taís Leite
authors: TL
authors: Seixas
authors: Cytogenetics Laboratory, Faculty of Medical Sciences, Rio de Janeiro State University (UERJ), Rio de Janeiro 20551-120, Brazil; Department of Medical Genetic, Fernandes Figueira Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 22250-020, Brazil.
authors: Elenice Ferreira
authors: EF
authors: Bastos
authors: Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, D-07743 Jena, Germany.
authors: Thomas
authors: T
authors: Liehr
authors: Department of Pathology, Laboratory of Circulating Markers, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil; Graduation Course in Medical Sciences, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil; Research Coordination, National Cancer Institute (INCA), Ministry of Health, Rio de Janeiro 20230-130, Brazil.
authors: Gilda
authors: G
authors: Alves
keywords: Janus kinase 2 gene; aging; complex karyotype; essential thrombocythemia; myelodysplastic syndrome