title: Venous thrombosis in children and adolescents with Hodgkin lymphoma in Sweden.
abstract: BACKGROUND
  Pediatric patients with Hodgkin lymphoma (HL) have several risk factors for venous thromboembolism (VTE). Although these patients are occasionally treated with thromboprophylaxis, no guidelines are implemented in Sweden. Scarce data from adult patients indicate an increased risk of VTE, but pediatric data is largely missing. Given the favorable overall survival of HL, there should reasonably be more focus on preventing complications.
  
  
  METHODS
  We conducted a retrospective cohort study, including all patients registered in the Childhood Cancer Registry under the age of 18years diagnosed with HL between January 2005 and December 2015 in Sweden.
  
  
  RESULTS
  Data was retrieved from the medical records of all 163 patients (100%) at six Swedish pediatric cancer centers. The incidence of VTE was 7.7% (symptomatic VTE 3.9%). The median follow-up was 3.4years (range 0.3-10.5). Only five patients (3.1%) were treated with thromboprophylaxis. All VTE events occurred in the older age category (11-17years) and all but one (92.7%) had a mediastinal mass. While the VTE did not significantly affect the treatment of HL, it caused increased morbidity and 2/12 developed a post-thrombotic syndrome. No significant risk factors for VTE were identified.
  
  
  CONCLUSIONS
  VTE is a relatively common complication of HL and its treatment, causing increased acute and long-term morbidity. However, due to limited number of events we could not demonstrate risk-factors for VTE that would identify patients who might benefit from thromboprophylaxis.
authors.affiliation: Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Schönning
authors.affiliation: Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Karlén
authors.affiliation: Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Frisk
authors.affiliation: Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Heyman
authors.affiliation: Pediatric Oncology, Skåne University Hospital, Lund University, Sweden.
authors.forename: J E
authors.initials: JE
authors.lastname: Svahn
authors.affiliation: Pediatric Oncology, Skåne University Hospital, Lund University, Sweden.
authors.forename: I
authors.initials: I
authors.lastname: Øra
authors.affiliation: Children's Cancer Center, Queen Silvia Children's Hospital, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Kawan
authors.affiliation: Department of Pediatrics, Linköping University Hospital, Linköping, Sweden.
authors.forename: B-M
authors.initials: BM
authors.lastname: Holmqvist
authors.affiliation: Department of Pediatric Hematology and Oncology, Umeå University Hospital, Umeå, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Björklund
authors.affiliation: Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Harila-Saari
authors.affiliation: Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska University Hospital and Karolinska Institute, Stockholm, Sweden. Electronic address: susanna.ranta@ki.se.
authors.forename: S
authors.initials: S
authors.lastname: Ranta
mesh_terms: D000293:Adolescent; D000925:Anticoagulants / Q000627:therapeutic use; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006495:Heparin, Low-Molecular-Weight / Q000627:therapeutic use; D006689:Hodgkin Disease / Q000150:complications*; D006801:Humans; D015994:Incidence; D012189:Retrospective Studies; D013548:Sweden / Q000453:epidemiology; D020246:Venous Thrombosis / Q000188:drug therapy* / Q000453:epidemiology*
chemical_list: D000925:Anticoagulants; D006495:Heparin, Low-Molecular-Weight
keywords: Adolescents; Children; Hodgkin lymphoma; Venous thromboembolism