title: Familial aggregation of Hodgkin lymphoma and related tumors.
abstract: BACKGROUND
  The importance of genetic factors in the etiology of Hodgkin lymphoma (HL) has been suggested by family and population studies. However, the spectrum of malignancies associated with common genetic etiology and the effects of gender and age on familial risk have not been established.
  
  
  METHODS
  Diagnoses of lymphoproliferative malignancies were compared in 15,799 first-degree relatives of 5047 patients with HL versus 32,117 first-degree relatives of 10,078 control probands from Sweden and in 7185 first-degree relatives of 2429 patients with HL versus 27,434 first-degree relatives of 8,495 control probands from Denmark using marginal survival models.
  
  
  RESULTS
  The risk of HL in relatives of patients with HL was increased significantly in both populations, with relative risks of 3.47 (95% confidence interval [95% CI], 1.77-6.80) in Sweden and 2.55 (95% CI, 1.01-6.45) in Denmark and a pooled estimate of 3.11 (95%CI, 1.82-5.29). In Sweden, risks for relatives of patients also were increased significantly for chronic lymphocytic leukemia and non-Hodgkin lymphoma (in males). Relative risks were higher in males compared with females and in siblings of patients compared with parents and offspring of patients. Relatives of patients with earlier-onset disease were at higher risk for HL.
  
  
  CONCLUSIONS
  HL has an important familial component, which is stronger in families of affected individuals age < 40 years, in males, and in siblings, and it is shared with some (but not other) lymphoproliferative malignancies. The cumulative lifetime risks are very small, however, for the development of HL de novo or in first-degree relatives of affected patients.
authors.affiliation: Genetic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-7236, USA. goldinl@mail.nih.gov
authors.forename: Lynn R
authors.initials: LR
authors.lastname: Goldin
authors.forename: Ruth M
authors.initials: RM
authors.lastname: Pfeiffer
authors.forename: Gloria
authors.initials: G
authors.lastname: Gridley
authors.forename: Mitchell H
authors.initials: MH
authors.lastname: Gail
authors.forename: Xinjun
authors.initials: X
authors.lastname: Li
authors.forename: Lene
authors.initials: L
authors.lastname: Mellemkjaer
authors.forename: Jørgen H
authors.initials: JH
authors.lastname: Olsen
authors.forename: Kari
authors.initials: K
authors.lastname: Hemminki
authors.forename: Martha S
authors.initials: MS
authors.lastname: Linet
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D016022:Case-Control Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D020022:Genetic Predisposition to Disease; D019337:Hematologic Neoplasms / Q000453:epidemiology / Q000235:genetics; D006689:Hodgkin Disease / Q000453:epidemiology* / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D015995:Prevalence; D011336:Probability; D016016:Proportional Hazards Models; D012042:Registries; D018570:Risk Assessment; D017678:Sex Distribution; D013548:Sweden / Q000453:epidemiology