Risk of familial classical Hodgkin lymphoma by relationship, histology, age, and sex: A joint study from five Nordic countries.

• The rarity of familial Hodgkin lymphoma (HL) has hampered detailed analyses of familial clustering. We aimed to provide the familial risk of HL by relationship, histology, age at diagnosis and sex. A cohort of 57,475 first-degree relatives of 13,922 HL patients, diagnosed between 1955 and 2009, in five European countries was followed for HL incidence. Standardized incidence ratios (SIRs) were calculated using histology-, age-, sex-, period-, and country-specific incidence rates as the reference. The lifetime cumulative risks (CR) were also calculated. The overall CR of HL in first-degree relatives of a patient with HL was 0.6%, which represents a 3-fold (SIR=3.3, 95%CI=2.8-3.9) increased risk over the general population risk. The risk in siblings (6.0-fold; 4.8-7.4) was significantly higher than in parents/children (2.1-fold; 1.6-2.6). Very high lifetime risk of HL was found for those with multiple affected first-degree relatives (13-fold; 2.8-39) and for same-sex twins (57-fold; 21-125). We found high familial risks between some concordant histological subtypes of HL [lymphocyte-rich (81-fold, 30-177) and nodular sclerosis (4.6-fold, 2.9-7.0)] and also between some discordant subtypes. The familial risk in sisters (9.4-fold; 5.9-14) was higher than in brothers (4.5-fold; 2.9-6.7) or unlike-sex siblings (5.9-fold; 4.3-8.1). The lifetime risk of HL was higher when first-degree relatives were diagnosed at early ages (before age 30). This study provides tangible absolute risk estimates for relatives of HL patients, which can be used as a sex-, age-, and family history-based risk calculator for classical Hodgkin lymphoma by oncologists and genetic counselors.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Hematologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Hematology (hsv//eng)

Publication and Content Type

art (subject category)

ref (subject category)