title: Clinical features and course of refractory anemia with ring sideroblasts associated with marked thrombocytosis.
abstract: BACKGROUND
  Refractory anemia with ring sideroblasts associated with marked thrombocytosis was proposed as a provisional entity in the 2001 World Health Organization classification of myeloid neoplasms and also in the 2008 version, but its existence as a single entity is contested. We wish to define the clinical features of this rare myelodysplastic/myeloproliferative neoplasm and to compare its clinical outcome with that of refractory anemia with ring sideroblasts and essential thrombocythemia.
  
  
  METHODS
  We conducted a collaborative retrospective study across Europe. Our database included 200 patients diagnosed with refractory anemia with ring sideroblasts and marked thrombocytosis. For each of these patients, each patient diagnosed with refractory anemia with ring sideroblasts was matched for age and sex. At the same time, a cohort of 454 patients with essential thrombocythemia was used to compare outcomes of the two diseases.
  
  
  RESULTS
  In patients with refractory anemia with ring sideroblasts and marked thrombocytosis, depending on the Janus Kinase 2 V617F mutational status (positive or negative) or platelet threshold (over or below 600 × 10(9)/L), no difference in survival was noted. However, these patients had shorter overall survival and leukemia-free survival with a lower risk of thrombotic complications than did patients with essential thrombocythemia (P<0.001) but better survival (P<0.001) and a higher risk of thrombosis (P=0.039) than patients with refractory anemia with ring sideroblasts.
  
  
  CONCLUSIONS
  The clinical course of refractory anemia with ring sideroblasts and marked thrombocytosis is better than that of refractory anemia with ring sideroblasts and worse than that of essential thrombocythemia. The higher risk of thrombotic events in this disorder suggests that anti-platelet therapy might be considered in this subset of patients. From a clinical point of view, it appears to be important to consider refractory anemia with ring sideroblasts and marked thrombocytosis as a distinct entity.
authors.affiliation: Service d'Hématologie Biologique, Hôpital du Bocage, CHU de Dijon, Dijon, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Broseus
authors.forename: Lourdes
authors.initials: L
authors.lastname: Florensa
authors.forename: Esther
authors.initials: E
authors.lastname: Zipperer
authors.forename: Susanne
authors.initials: S
authors.lastname: Schnittger
authors.forename: Luca
authors.initials: L
authors.lastname: Malcovati
authors.forename: Steven
authors.initials: S
authors.lastname: Richebourg
authors.forename: Eric
authors.initials: E
authors.lastname: Lippert
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Cermak
authors.forename: Jyoti
authors.initials: J
authors.lastname: Evans
authors.forename: Morgane
authors.initials: M
authors.lastname: Mounier
authors.forename: José Maria
authors.initials: JM
authors.lastname: Raya
authors.forename: François
authors.initials: F
authors.lastname: Bailly
authors.forename: Norbert
authors.initials: N
authors.lastname: Gattermann
authors.forename: Torsten
authors.initials: T
authors.lastname: Haferlach
authors.forename: Richard
authors.initials: R
authors.lastname: Garand
authors.forename: Kaoutar
authors.initials: K
authors.lastname: Allou
authors.forename: Carlos
authors.initials: C
authors.lastname: Besses
authors.forename: Ulrich
authors.initials: U
authors.lastname: Germing
authors.forename: Claudia
authors.initials: C
authors.lastname: Haferlach
authors.forename: Erica
authors.initials: E
authors.lastname: Travaglino
authors.forename: Elisa
authors.initials: E
authors.lastname: Luno
authors.forename: Maria Angeles
authors.initials: MA
authors.lastname: Pinan
authors.forename: Leonor
authors.initials: L
authors.lastname: Arenillas
authors.forename: Maria
authors.initials: M
authors.lastname: Rozman
authors.forename: Maria Luz
authors.initials: ML
authors.lastname: Perez Sirvent
authors.forename: Bernardine
authors.initials: B
authors.lastname: Favre
authors.forename: Julien
authors.initials: J
authors.lastname: Guy
authors.forename: Esther
authors.initials: E
authors.lastname: Alonso
authors.forename: Nuhri
authors.initials: N
authors.lastname: Ahwij
authors.forename: Andrés
authors.initials: A
authors.lastname: Jerez
authors.forename: Sylvie
authors.initials: S
authors.lastname: Hermouet
authors.forename: Marc
authors.initials: M
authors.lastname: Maynadié
authors.forename: Mario
authors.initials: M
authors.lastname: Cazzola
authors.forename: François
authors.initials: F
authors.lastname: Girodon
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000753:Anemia, Refractory / Q000150:complications / Q000401:mortality / Q000473:pathology*; D000756:Anemia, Sideroblastic / Q000150:complications / Q000401:mortality / Q000473:pathology*; D001792:Blood Platelets / Q000473:pathology; D005060:Europe; D005260:Female; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010976:Platelet Count; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D013920:Thrombocythemia, Essential / Q000150:complications / Q000401:mortality / Q000473:pathology*; D013922:Thrombocytosis / Q000150:complications / Q000401:mortality / Q000473:pathology*
chemical_list: C507924:JAK2 protein, human; D053614:Janus Kinase 2