Chronic Sinusitis and Risk of Head and Neck Cancer in the US Elderly Population

IMPORTANCE: Chronic sinusitis may be involved in the etiology of certain head and neck cancers (HNCs), due to immunodeficiency or inflammation. However, the risk of specific HNCs among people with chronic sinusitis is largely unknown. OBJECTIVE: To evaluate the associations of chronic sinusitis with subsequent HNC, including nasopharyngeal cancer (NPC), human papillomavirus–related oropharyngeal cancer (HPV-OPC), and nasal cavity and paranasal sinus cancer (NCPSC), in an elderly US population. DESIGN, SETTING, AND PARTICIPANTS: We used the Surveillance, Epidemiology, and End Results (SEER)-Medicare database to conduct a case-cohort study of US individuals aged 65 years or older during 2004 through 2011. The study included 483 546 Medicare beneficiaries from SEER areas in a 5% random subcohort, and 826 436 from the entire source population who developed cancer (including 21 716 with HNC). MAIN OUTCOMES AND MEASURES: Incidence of HNCs including NPC, HPV-OPC, and NCPSC. RESULTS: Most individuals were female (57.7%), and the mean (SD) age at entry was 72.6 (8.0) years. Chronic sinusitis was associated with risk of developing HNC (adjusted hazard ratio [aHR], 1.37; 95% CI, 1.27-1.48), particularly NPC (aHR, 3.71; 95% CI, 2.75-5.02), HPV-OPC (aHR, 1.33; 95% CI, 1.13-1.57), and NCPSC (aHR, 5.49; 95% CI, 4.56-6.62). Most of this increased risk was limited to risk within 1 year of the chronic sinusitis diagnosis, as associations were largely attenuated 1 year or more after chronic sinusitis (NPC: aHR, 1.60; 95% CI, 0.96-2.65; HPV-OPC: aHR, 1.07; 95% CI, 0.86-1.32; NCPSC: aHR, 2.47; 95% CI, 1.84-3.31). All 3 HNC subtypes had cumulative incidence of less than 0.07% 8 years after chronic sinusitis diagnosis. CONCLUSIONS AND RELEVANCE: Chronic sinusitis is associated with certain HNCs, particularly NPC and NCPSC. These HNCs are rare, and most of the increased HNC risk is limited to within 1 year of chronic sinusitis diagnosis, consistent with surveillance or detection bias. The associations were weaker over longer intervals, suggesting at most a modest role for sinusitis-related inflammation and/or immunodeficiency.