Abstract A30: Association of pretreatment BMI with risk of head and neck cancer: A large-scale single-center study
Authors: Khanna Anshu , Sturgis Eric , Xu Li , Wei Qingyi , Li Guojun , Gross Neil 
Published: September 2020

Abstract
Background: Tobacco and alcohol exposure are the dominant risk factors for the development of squamous cell cancer of the head and neck (SCCHN) worldwide. While human papilloma virus (HPV) is strongly associated with oropharyngeal SCCHN, much less is known about the role of obesity. Body mass index (BMI) has been implicated as a potential risk factor for SCCHN, yet the data available so far have demonstrated mixed results. Therefore, we conducted the largest case-control study to date to examine the potential association of risk of SCCHN with pretreatment BMI.
Methods: BMI, clinical, and patient-reported epidemiologic information at diagnosis were collected among 2,310 SCCHN cases and 1,915 cancer-free controls from October 2001 to May 2013. Cases included cancers of the oral cavity, oropharynx, and hypopharynx/larynx. Logistic regression analysis was used to assess odds ratios (OR) with 95% confidence intervals (95% CIs). Multivariable-adjusted models were used to evaluate the association between BMI and SCCN risk, and further stratified analysis was performed.
Results: At diagnosis, 1.9% of the cases (patients) were underweight (BMI&lt;18.5), 25.7% were normal weight (BMI 18.5-&lt;25), 38.4% were overweight (BMI 25-&lt;30), and 34% were obese (BMI ≥30). Pretreatment BMI was significantly associated with increased risk of SCCHN in patients who were underweight (OR, 2.61; 95%CI, 1.46-4.66) and reduced risk of SCCHN in patients who were overweight (OR, 0.69; 95%CI, 0.59-0.8) or obese (OR, 0.77; 95%CI, 0.65-0.91), respectively. The observed increased risk associated with underweight patients was most pronounced among alcohol drinkers (OR, 3.55; 95% CI, 1.49 -8.47), smokers (OR, 2.52; 95% CI, 1.16 -5.45), oral cavity cancer patients (OR, 2.57; 95% CI, 1.33-4.96), oropharyngeal cancer patients (OR, 2.76; 95% CI, 1.39-5.47), and hypopharyngeal/laryngeal cancer patients (OR, 3.21; 95% CI, 1.35-7.62). For obese patients, a significantly protective effect was found among smokers (OR, 0.59; 95% CI, 0.47 -0.74), alcohol drinkers (OR, 0.68; 95% CI, 0.55-0.84), oral cavity cancer patients (OR, 0.61; 95% CI, 0.48-0.76), oropharyngeal cancer patients (OR, 0.87; 95% CI, 0.71-1.07), and hypopharyngeal/laryngeal cancer patients (OR, 0.63; 95% CI, 0.47-0.86).
Conclusion: The present findings suggest that pretreatment BMI is a significant independent risk factor for SCCHN. Increased BMI at diagnosis confers reduced risk while decreased BMI has increased risk for SCCHN. The mechanism for the inverse association between pretreatment BMI and risk of SCCHN has yet to be elucidated.
Citation Format: Anshu Khanna, Eric Sturgis, Li Xu, Qingyi Wei, Guojun Li, Neil Gross. Association of pretreatment BMI with risk of head and neck cancer: A large-scale single-center study [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; 2019 Apr 29-30; Austin, TX. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(12_Suppl_2):Abstract nr A30.