title: Management of extreme thrombocytosis in myeloproliferative neoplasms: an international physician survey.
abstract: Extreme thrombocytosis (ExT) has been associated with an increased bleeding risk in myeloproliferative neoplasm (MPN) patients and is included in the high risk category in treatment guidelines. Treatment of patients with ExT has not been studied in prospective trials. To study physicians' approaches to ExT, we distributed a web based questionnaire with clinical case scenarios to 202 members of MPN working groups. Cases included low thrombotic risk essential thrombocythemia (ET) with either JAK2V617F or CALR mutation, polycythemia vera with ExT either with or without leukocytosis, an ET patient needing urgent orthopedic surgery, and a poorly controlled ET patient with acute cerebral venous sinus thrombosis. Responses were received from 90 physicians (45 %) and were variable in most case scenarios. Country of practice had the most significant influence on physician response. The USA and Israel physicians responded similarly in most cases and differently to the Europe physicians. Treatment of asymptomatic JAK2V617F positive ET and target platelet count on cytoreduction were significantly influenced by physician years of experience. Responses were not influenced by the volume of MPN practice or by whether MPN was considered a major interest by the physician. Our results show a lack of consensus on how to manage MPN patients with ExT. Randomized controlled trials properly designed to address these questions are needed.
authors.affiliation: Department of Hematology, Assaf Harofeh Medical Center, Zeriffin, 70300, Israel. korenm@asaf.health.gov.il.|Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel. korenm@asaf.health.gov.il.
authors.forename: Maya
authors.identifier: http://orcid.org/0000-0002-7223-328X
authors.initials: M
authors.lastname: Koren-Michowitz
authors.affiliation: Department of Hematology and Bone Marrow Transplantation, Rambam Health Care Campus, Haifa, Israel.
authors.forename: Noa
authors.initials: N
authors.lastname: Lavi
authors.affiliation: Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.|Meir Medical Center, Kfar Saba, Israel.
authors.forename: Martin H
authors.initials: MH
authors.lastname: Ellis
authors.affiliation: Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
authors.forename: Alessandro M
authors.initials: AM
authors.lastname: Vannucchi
authors.affiliation: Mayo Clinic, Scottsdale, AZ, USA.
authors.forename: Ruben
authors.initials: R
authors.lastname: Mesa
authors.affiliation: Department of Haematology, Guy's and St. Thomas' NHS Foundation Trust, London, UK.
authors.forename: Claire N
authors.initials: CN
authors.lastname: Harrison
mesh_terms: D000328:Adult; D000368:Aged; D019468:Disease Management; D005260:Female; D006801:Humans; D038622:Internationality; D008297:Male; D008875:Middle Aged; D009196:Myeloproliferative Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*; D010820:Physicians; D011795:Surveys and Questionnaires; D013922:Thrombocytosis / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy*
keywords: Acquired von Willebrand disease; Bleeding; Myeloproliferative neoplasm; Thrombocytosis