Birth order and risk of nasopharyngeal carcinoma in multiplex families from Taiwan. Issue 11 (30th August 2016)

• Record Type: Journal Article
• Authors: Liu, Zhiwei; Coghill, Anna E.; Pfeiffer, Ruth M.; Hsu, Wan‐Lun; Lou, Pei‐Jen; Wang, Cheng‐Ping; Yu, Kelly J.; Niwa, Shelley; Brotzman, Michelle; Ye, Weimin; Chen, Chien‐Jen; Hildesheim, Allan
• Is Part Of: International journal of cancer. Volume 139:Issue 11(2016:Dec. 01)
• Page Start: 2467
• Page End: 2473
• Publication Date: 2016-08-30
• Subjects: birth order -- Epstein–Barr virus -- multiplex family -- infant‐contact -- nasopharyngeal carcinoma -- Taiwan; Cancer -- Periodicals; Cancer -- Prevention -- Periodicals; 616.994
• DOI: 10.1002/ijc.30390
• Languages: English
• ISSNs: 0020-7136

Abstract

Abstract : A small proportion of individuals infected with Epstein–Barr virus (EBV) develop nasopharyngeal carcinoma (NPC). Timing of initial exposure could alter immunological responses to primary EBV infection and explain variation in cancer risk later in life. We measured early life family structure as a proxy for the timing of primary EBV infection to examine whether earlier age at infection alters NPC risk. We utilized data from 480 NPC cases and 1, 291 unaffected siblings from Taiwanese NPC multiplex families (≥ 2 family members with NPC, N = 2, 921). Information on birth order within the family was derived from questionnaires. We utilized logistic regression models to examine the association between birth order and NPC, accounting for correlations between relatives. Within these high‐risk families, older siblings had an elevated risk of NPC. Compared with being a first‐born child, the risk (95% CIs) of NPC associated with a birth order of two, three, four and five or more was 1.00 (0.71, 1.40), 0.88 (0.62, 1.24), 0.74 (0.53, 1.05) and 0.60 (0.43, 0.82), respectively ( P for trend = 0.002). We observed no associations between NPC risk and the number of younger siblings or cumulative infant‐years exposure. These associations were not modified by underlying genetic predisposition or family size. We observed that early life family structure was important for NPC risk in NPC multiplex families, with older siblings having a greater risk of disease. Future studies focusing on more direct measures of the immune response to EBV in early childhood could elucidate the underlying mechanisms. Abstract : What's new? Got cancer? Blame your baby siblings. New analysis suggests that being an older sibling increase your likelihood of developing nasopharyngeal cancer (NPC) in high‐risk populations. Infection with the Epstein‐Barr virus can lead to cancer later in life, but whether age at primary infection alters the risk of NPC in endemic areas is unknown. Using the presence of siblings as a proxy for early childhood exposure to the virus, these authors collected birth order information from NPC cases and controls in NPC multiplex families in Taiwan. They found that older siblings did have a higher incidence of NPC than subsequent children, suggesting that timing at EBV infection may pave the way for NPC later in life.