Abstract 2740: Familial Hodgkin lymphoma by relationship, sex, age and histology: a joint study from five Nordic countries

Abstract

Abstract Background: We aimed to estimate lifetime (0-79 years) cumulative risk (CR) of Hodgkin lymphoma (HL) in relatives of patients with HL by relationship, sex, age and histology. Design: A population-based cohort of 57,475 first-degree relatives of 13,922 HL patients diagnosed in 1955-2009 in Nordic countries was followed for cancer incidence. Standardized incidence ratios (SIRs) were calculated using histology-, age-, sex-, period-, and country-specific incidence rates as the reference. Results: The overall CR of HL in first-degree relatives of a patient with Hodgkin lymphoma was 0.6%, which represents 3-fold (SIR = 3.3, 95%CI = 2.8-3.9) increase over the general population risk (men 0.3%; women 0.2%). Significantly high CR (1%) was found among sisters with early-onset HL and unlike-sex siblings with HL diagnosed at age 30-59. The familial risk in sisters (9-fold) was higher than in brothers (4.5-fold) or unlike-sex siblings (6-fold). In general, the risk in siblings (6-fold) was higher than in parents/children (2-fold). Very high risk of HL was found for few men with two HL first-degree relatives (3-8%) and for twin brothers (18%). For the first time we found high familial risk of concordant histological subtypes of HL [lymphocyte-rich (81-fold, n = 6) and nodular sclerosis (4.6-fold, n = 22)] and also discordant subtypes. Conclusions: Lymphocytic-rich histology type of HL showed highest familial risk. The absolute risk of familial HL was generally less than 1.5%, except for men with multiple affected first-degree relatives (3-8%), twin brothers (18%), or brothers with early-onset HL (2%). Citation Format: Mahdi Fallah, Elham Kharazmi, Eero Pukkala, Jørgen H. Olsen, Laufey Tryggvadottir, Kristina Sundquist, Steinar Tretli, Kari Hemminki. Familial Hodgkin lymphoma by relationship, sex, age and histology: a joint study from five Nordic countries. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2740. doi:10.1158/1538-7445.AM2015-2740