title: High familial risk in nodular lymphocyte-predominant Hodgkin lymphoma.
abstract: OBJECTIVE
  Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is one of the two established Hodgkin lymphoma (HL) subtypes. The risk factors of NLPHL are largely unknown. In general, genetic factors are known to have a modest effect on the risk of HL; however, familial risk in NLPHL has not been previously examined. We conducted a population-based study by using the Finnish registries and evaluated the familial risk in NLPHL.
  
  
  METHODS
  We launched a population-based search to identify patients with NLPHL and their relatives by examining the records of the Finnish Cancer Registry, established in 1953, and the official Finnish population registries. We collected a data set of 692 patients with NLPHL, identified their 4,280 first-degree relatives, and calculated the registry-based standardized incidence ratios (SIRs) for different cancers in the first-degree relatives. In addition, the primary tumor biopsies of HL-affected relatives were collected when possible, the HL diagnoses were re-reviewed by a hematopathologist, and the SIR for NLPHL was calculated on the basis of confirmed NLPHL diagnoses.
  
  
  RESULTS
  On the basis of confirmed NLPHL diagnoses, the SIR for NLPHL was 19 (95% CI, 8.8 to 36) in the first-degree relatives. The risk was most prominent in female relatives of young patients. The registry-based SIR for classical HL was 5.3 (95% CI, 3.0 to 8.8), and for non-Hodgkin lymphoma, it was 1.9 (95% CI, 1.3 to 2.6).
  
  
  CONCLUSIONS
  Our results implicate an unexpectedly high familial component in the development of NLPHL. Research is warranted to identify the putative genetic and environmental factors underlying this finding and to develop strategies for better management of patients with NLPHL and their relatives.
authors.affiliation: University of Helsinki, Helsinki, Finland.
authors.forename: Silva
authors.initials: S
authors.lastname: Saarinen
authors.forename: Eero
authors.initials: E
authors.lastname: Pukkala
authors.forename: Pia
authors.initials: P
authors.lastname: Vahteristo
authors.forename: Markus J
authors.initials: MJ
authors.lastname: Mäkinen
authors.forename: Kaarle
authors.initials: K
authors.lastname: Franssila
authors.forename: Lauri A
authors.initials: LA
authors.lastname: Aaltonen
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005387:Finland / Q000453:epidemiology; D020022:Genetic Predisposition to Disease; D006689:Hodgkin Disease / Q000235:genetics* / Q000473:pathology*; D006801:Humans; D015994:Incidence; D008214:Lymphocytes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors