Medical History,medication Use,and Risk Of Nasopharyngeal Carcinoma

Background Because persistent inflammation and infection,a hallmark of cancer,may render the nasopharyngeal mucosa susceptible to carcinogenesis,chronic ear/nose/throat disease and related drug use might influence the risk of nasopharyngeal carcinoma(NPC).Existing evidence is,however,inconclusive and often based on methodologically suboptimal epidemiologic studies.Objective To explore the relationship between the chronic ear/nose/throat disease,related medication use,and risk of nasopharyngeal carcinoma.Methods Gene-environment-EBV Interactions in the Etiology of Nasopharyngeal Carcinoma(NPCGEE)is a collaborative population-based case-control study of NPC based in the Zhaoqing area of Guangdong Province,and the Wuzhou and Guiping/Pingnan areas of Guangxi Autonomous Region.These areas encompass 13 cities/counties (Deqing,Fengkai,Gaoyao,Huaiji,Sihui,Zhaoqing,Guangning,Wuzhou,Cenxi,Cangwu,Tengxian,Pingnan,and Guiping)in southern China,with a total population of approximately 8 million.We enrolled 2532 NPC cases and 2597 controls aged 20-74 years between 2010 and 2014.Our study is based on the data collected from questionnaire about chronic ear/nose/throat disease(chronic sinusitis,chronic otitis,chronic pharyngitis,nasal polyps,and septal abnormalities)and related drug use(nasal drops or aspirin),and used unconditional logistic regression to estimate multivariate-adjusted odds ratios(ORs)with 95% confidence intervals(CIs),to explore the relationship between the chronic ear/nose/throat disease,related medication use,and risk of NPC.Results Any history of chronic ear/nose/throat(ENT)disease(chronic sinusitis,chronic otitis,chronic pharyngitis,nasal polyps,and septal abnormalities)was associated with a 34% increased risk of NPC(OR=1.34,95%CI:1.12-1.59).Similarly,a history of use of nasal drops or aspirin was associated with a close to doubled risk of NPC(OR=1.98,95%CI:1.31-3.01;OR=1.91,95%CI:1.52-2.41).However,in order to exclude reverse causality in secondary analyses restricted to chronic ENT diseases and related medication use at least 5 years prior to diagnosis/interview,most results were statistically non-significant,except a history of uncured ENT diseases(OR = 1.28,95% CI :1.00-1.64), untreated nasal polyp(OR=3.26,95% CI:1.14-9.34),older age(>23)at the most recent diagnosis of chronic otitis(OR = 2.05,95% CI: 1.06,3.97),early age(<31)at first diagnosis of ENT disease(OR=1.35,95% CI:1.04-1.76)and initiation(<37)or most recent use(<50)of aspirin in young age(OR = 1.68,95%CI: 1.13-2.52,and OR = 1.68,95% CI: 1.08-2.60,respectively).Conclusion These findings suggest that ENT disease and related medication use modestly increase risk of NPC,but it is possible an influence of reverse causality and/or recall bias.