title: Proposed diagnostic criteria and classification of basophilic leukemias and related disorders.
abstract: Basophils form a distinct cell lineage within the hematopoietic cell family. In various myeloid neoplasms, including chronic myeloid leukemia, basophilia is frequently seen. Acute and chronic basophilic leukemias, albeit rare, have also been described. However, no generally accepted criteria and classification of basophilic leukemias have been presented to date. To address this unmet need, a series of Working Conferences and other meetings were organized between March 2015 and March 2016. The current article provides a summary of consensus statements from these meetings, together with proposed criteria to delineate acute basophilic leukemia (ABL) from chronic basophilic leukemia (CBL) and primary forms of the disease where no preceding myeloid malignancy is detected, from the more common 'secondary' variants. Moreover, the term hyperbasophilia (HB) is proposed for cases with a persistent peripheral basophil count ⩾1000 per μl of blood. This condition, HB, is highly indicative of the presence of an underlying myeloid neoplasm. Therefore, HB is an important checkpoint in the diagnostic algorithm and requires a detailed hematologic investigation. In these patients, an underlying myeloid malignancy is often found and is then labeled with the appendix -baso, whereas primary cases of ABL or CBL are very rare. The criteria and classification proposed in this article should facilitate the diagnosis and management of patients with unexplained basophilia and basophil neoplasms in routine practice, and in clinical studies.
authors.affiliation: Department of Internal Medicine I, Division of Hematology and Hemostaseology and Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.|Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
authors.forename: P
authors.initials: P
authors.lastname: Valent
authors.affiliation: Institute of Pathology, Paracelsus Medical University Salzburg, Salzburg, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Sotlar
authors.affiliation: Department of Internal Medicine I, Division of Hematology and Hemostaseology and Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.|Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Blatt
authors.affiliation: Department of Dermatology, University of Luebeck, Luebeck, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Hartmann
authors.affiliation: Department of Hematology and Oncology, University Medical Center Mannheim, University of Heidelberg, Mannheim, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Reiter
authors.affiliation: Department of Internal Medicine I, Division of Hematology and Hemostaseology and Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
authors.forename: I
authors.initials: I
authors.lastname: Sadovnik
authors.affiliation: Department of Internal Medicine I, Division of Hematology and Hemostaseology and Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.|Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
authors.forename: W R
authors.initials: WR
authors.lastname: Sperr
authors.affiliation: Division of Laboratory Medicine, Elisabethinen Hospital Linz, Linz, Austria.
authors.forename: P
authors.initials: P
authors.lastname: Bettelheim
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Harvard Medical School, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: C
authors.initials: C
authors.lastname: Akin
authors.affiliation: Department of Internal Medicine I, Division of Hematology and Hemostaseology and Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Bauer
authors.affiliation: Department of Pathology, University of New Mexico, Albuquerque, NM, USA.
authors.forename: T I
authors.initials: TI
authors.lastname: George
authors.affiliation: Department of Internal Medicine I, Division of Hematology and Hemostaseology and Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.|Ludwig Boltzmann Cluster Oncology, Medical University of Vienna, Vienna, Austria.
authors.forename: E
authors.identifier: 0000-0001-7409-4204
authors.initials: E
authors.lastname: Hadzijusufovic
authors.affiliation: Medical Clinic III for Oncology, Haematology and Rheumatology, University Hospital Bonn, Bonn, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Wolf
authors.affiliation: Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: J
authors.initials: J
authors.lastname: Gotlib
authors.affiliation: Laboratoire d'Hématologie, CHU de Bordeaux, France.
authors.forename: F-X
authors.initials: FX
authors.lastname: Mahon
authors.affiliation: Laboratory of Allergic Diseases, NIAID, NIH, Bethesda, MD, USA.
authors.forename: D D
authors.initials: DD
authors.lastname: Metcalfe
authors.affiliation: Institute of Pathology, Ludwig-Maximilians University, Munich, Germany.
authors.forename: H-P
authors.initials: HP
authors.lastname: Horny
authors.affiliation: LBPA CNRS UMR8113, Ecole Normale Supérieure de Cachan, Cachan, France.
authors.forename: M
authors.initials: M
authors.lastname: Arock
mesh_terms: D000465:Algorithms; D001491:Basophils / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D015415:Biomarkers; D002454:Cell Differentiation; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D003582:Cytogenetics / Q000379:methods; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D015471:Leukemia, Basophilic, Acute / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism / Q000628:therapy; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism / Q000628:therapy; D007958:Leukocyte Count; D007960:Leukocyte Disorders / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism / Q000628:therapy; D010641:Phenotype
chemical_list: D015415:Biomarkers