{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T20:17:35Z","timestamp":1791145055780,"version":"4.1.0"},"reference-count":17,"publisher":"American Society of Clinical Oncology (ASCO)","issue":"16","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCO"],"published-print":{"date-parts":[[2008,6,1]]},"abstract":"<jats:sec><jats:title>Purpose<\/jats:title><jats:p> Established risk factors for thrombosis in essential thrombocythemia (ET) include age and previous vascular events. We aimed to refine this risk stratification by adding baseline leukocytosis. <\/jats:p><\/jats:sec><jats:sec><jats:title>Patients and Methods<\/jats:title><jats:p> We enrolled 657 patients with ET followed for a median of 4.5 years who developed 72 major thrombosis. Cox proportional hazard model was performed to analyze the thrombotic risk and to discriminate ET patients with or without thrombosis, multivariable C statistic index was used. We searched for leukocytes cutoff with the best sensitivity and specificity by a receiver operating characteristic curve. <\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p> Results confirmed that age and prior events are independent risk factors for thrombosis and showed a gradient between baseline leukocytosis and thrombosis. On the contrary, no significant association was found either for JAK2<jats:sup>V617F<\/jats:sup> allele burden and for other laboratory parameters, including platelet number. In the model with conventional risk factors alone, C statistic ratio for total thrombosis was 0.63 and when leukocytosis was added, the change was small (C = 0.67). In contrast, in younger and asymptomatic patients (low-risk category), C statistic value indicated an high risk for thrombosis in patients with leukocytosis, similar to that calculated in conventionally defined high-risk group (C = 0.65). The best leukocyte cutoff values for predicting the events was found to be 9.4 (\u00d7 10<jats:sup>9<\/jats:sup>\/L). <\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p> We suggest to include baseline leukocytosis in the risk stratification of ET patients enrolled in clinical trials. <\/jats:p><\/jats:sec>","DOI":"10.1200\/jco.2007.15.3569","type":"journal-article","created":{"date-parts":[[2008,4,29]],"date-time":"2008-04-29T01:26:47Z","timestamp":1209432407000},"page":"2732-2736","source":"Crossref","is-referenced-by-count":152,"title":["Leukocytosis and Risk Stratification Assessment in Essential Thrombocythemia"],"prefix":"10.1200","volume":"26","author":[{"given":"Alessandra","family":"Carobbio","sequence":"first","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabetta","family":"Antonioli","sequence":"additional","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paola","family":"Guglielmelli","sequence":"additional","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro M.","family":"Vannucchi","sequence":"additional","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federica","family":"Delaini","sequence":"additional","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vittoria","family":"Guerini","sequence":"additional","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guido","family":"Finazzi","sequence":"additional","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Rambaldi","sequence":"additional","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tiziano","family":"Barbui","sequence":"additional","affiliation":[{"name":"From the Hematology Department, Ospedali Riuniti di Bergamo; Hematology Department, Universit\u00e0 degli Studi di Firenze; Transfusion Medicine Department, Ospedali Riuniti di Bergamo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"233","reference":[{"key":"R1","doi-asserted-by":"publisher","DOI":"10.1200\/JCO.1990.8.3.556"},{"key":"R2","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa043800"},{"key":"R3","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2006-12-064287"},{"key":"R4","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2006-09-046342"},{"key":"R5","doi-asserted-by":"publisher","DOI":"10.1038\/sj.leu.2404500"},{"key":"R6","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2007-01-066985"},{"key":"R7","doi-asserted-by":"publisher","DOI":"10.1002\/sim.1802"},{"key":"R8","doi-asserted-by":"publisher","DOI":"10.1002\/(SICI)1097-0258(19960229)15:4<361::AID-SIM168>3.0.CO;2-4"},{"key":"R9","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa055373"},{"key":"R10","doi-asserted-by":"publisher","DOI":"10.1002\/sim.2427"},{"key":"R11","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2006-01-0254"},{"key":"R12","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2006-08-042515"},{"key":"R13","doi-asserted-by":"publisher","DOI":"10.1016\/j.exphem.2007.01.053"},{"key":"R14","doi-asserted-by":"publisher","DOI":"10.1161\/01.ATV.0000156877.94472.a5"},{"key":"R15","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMp068249"},{"key":"R16","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.319.7224.1562"},{"key":"R17","unstructured":"Barbui T, Barosi G, Grossi A, et al: Practice guidelines for the therapy of essential thrombocythemia: A statement from the Italian Society of Hematology, the Italian Society of Experimental Hematology and the Italian Group for Bone Marrow Transplantation. Haematologica 89:215,2004-232,"}],"container-title":["Journal of Clinical Oncology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/ascopubs.org\/doi\/pdfdirect\/10.1200\/JCO.2007.15.3569","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,5,25]],"date-time":"2022-05-25T20:17:00Z","timestamp":1653509820000},"score":1,"resource":{"primary":{"URL":"https:\/\/ascopubs.org\/doi\/10.1200\/JCO.2007.15.3569"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2008,6,1]]},"references-count":17,"journal-issue":{"issue":"16","published-print":{"date-parts":[[2008,6,1]]}},"alternative-id":["10.1200\/JCO.2007.15.3569"],"URL":"https:\/\/doi.org\/10.1200\/jco.2007.15.3569","relation":{},"ISSN":["0732-183X","1527-7755"],"issn-type":[{"value":"0732-183X","type":"print"},{"value":"1527-7755","type":"electronic"}],"subject":[],"published":{"date-parts":[[2008,6,1]]}}}