title: IPSET-Thrombosis Better Identifies Thrombosis-Free Survival: A Turkish Cohort.
abstract: BACKGROUND
  Essential thrombocythemia (ET) is the most common of the myeloproliferative neoplasms. For better predicting the occurrence of thrombotic events, an International Prognostic Score of Thrombosis for ET (IPSET-Thrombosis) was recently developed. We aimed to investigate the validity of IPSET-Thrombosis in a Turkish patient cohort and to compare the efficacy of IPSET-Thrombosis and conventional risk scoring systems in predicting thrombosis-free survival.
  
  
  METHODS
  We retrospectively evaluated the clinical characteristics and risk factors for thrombosis in 112 Turkish patients. Median thrombosis-free survival and Harrell C concordance indexes were calculated for both conventional and IPSET-Thrombosis.
  
  
  RESULTS
  Median age of 112 patients included in the study was 61 (range, 27-90) years at the time of diagnosis. When patients were stratified according to the conventional risk stratification system, 43.8% of patients were in the low-risk group and 56.2% in the high-risk group. A total of 22.4% of low-risk and 42.9% of high-risk patients had at least one thromboembolic event. When patients were stratified according to the IPSET-Thrombosis, 33% were in the low-risk group, 26.8% in the intermediate-risk group, and 40.2% in the high-risk group. Considering IPSET-Thrombosis risk groups, 5.4% of low-risk, 26.7% of intermediate-risk, and 66.2% of high-risk patients had at least one thromboembolic event. Regarding IPSET-Thrombosis risk groups, 10-year thrombosis-free survival was 86.8% for low-risk, 39.4% for intermediate-risk, and 32.9% for high-risk groups (P < .001). Harrell C concordance indexes of conventional and IPSET-Thrombosis were 0.60 and 0.77, respectively.
  
  
  CONCLUSIONS
  By validating the reproducibility of IPSET-Thrombosis in Turkish ET patients, we found that IPSET-Thrombosis identifies thrombosis-free survival better than the conventional risk stratification system.
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey. Electronic address: omurgok17@hotmail.com.
authors: Omur Gokmen
authors: OG
authors: Sevindik
authors: Department of Internal Medicine, Dokuz Eylul University, Izmir, Turkey.
authors: Sinan
authors: S
authors: Mersin
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Abdullah
authors: A
authors: Katgi
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Sunay
authors: S
authors: Tunali
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Serife Medeni
authors: SM
authors: Solmaz
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Celal
authors: C
authors: Acar
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Inci
authors: I
authors: Alacacioglu
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Ozden
authors: O
authors: Piskin
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Mehmet Ali
authors: MA
authors: Ozcan
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Fatih
authors: F
authors: Demirkan
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Bulent
authors: B
authors: Undar
authors: Department of Hematology, Dokuz Eylul University, Izmir, Turkey.
authors: Guner Hayri
authors: GH
authors: Ozsan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D013920:Thrombocythemia, Essential / Q000150:complications*; D013927:Thrombosis / Q000209:etiology*; D014421:Turkey
keywords: Essential thrombocythemia; IPSET-Thrombosis; Thromboembolism; Thrombosis-free survival; Turkey