Risk of nasopharyngeal carcinoma penetrates across immigrant generations: A migrant cohort study of 2.3 million Jewish Israeli adolescents

Abstract

Nasopharyngeal cancer (NPC) incidence varies widely across geographic regions and ethnic groups. We conducted a large-scale migrant cohort study to assess origin and migrant generation as predictors of NPC, controlling for possible confounders. Data on 2.3 million Jewish Israeli adolescents, who underwent a compulsory general health examination at ages 16–19 between the years 1967 and 2011 were linked to the Israel National Cancer Registry to obtain incident NPC up to 2012. Cox proportional hazards were used to model time to event. During 46.5 million person-years of follow-up, 276 incident cases were identified. Origin was a strong independent predictor of NPC with high rates for first generation North African born (adjusted HR 5.52; 95% CI 2.43–12.52; p < 0.000044) and Asian born (adjusted HR 3.79; 95% CI 1.43–10.00; p = 0.007) compared to European-born, adjusted for sex, year of birth, residential socio-economic position, years of education, rural residence, body mass index and height. The magnitude of the associations was similar in the Israeli-born of North African and Asian origin, with these second and third generation immigrants showing elevated HRs (adjusted HR 6.09; 95% CI 2.81–13.20; p = 4.72.10−6 and 3.86; 95% CI 1.77–8.41; p = 0.00067, respectively). These findings suggest a strong genetic predisposition and/or efficient cultural transmission of environmental exposures in the etiology of NPC.