title: A Comprehensive Analysis on the Association between Tobacco-Free Betel Quid and Risk of Head and Neck Cancer in Taiwanese Men.
abstract: OBJECTIVE
  Although betel quid (BQ) is an established risk factor of head and neck cancer (HNC), insufficiencies exist in the literature regarding the dose-response, BQ types, HNC sites, and BQ cessation. The current study was conducted to fill these insufficiencies.
  
  
  METHODS
  A hospital-based case-control study was conducted to evaluate the association between BQ and HNC. In-person interview was conducted to collect data on BQ chewing. The current analysis included 487 men newly diagnosed with HNC and 617 male controls who were frequency-matched to the cases by age. The association between BQ and HNC was assessed using multivariable unconditional logistic regression.
  
  
  RESULTS
  Ever BQ chewing was associated with an increased HNC risk regardless of the BQ types. A non-linear positive association between BQ and HNC was observed, with a steep rise in HNC risk for the first 5 pack-years or 200,000 minutes of BQ consumption. Every year of BQ cessation was associated with a 2.9% reduction in HNC risk; however, the risk did not reduce to the level of non-BQ chewers even after 20 years of BQ cessation. Eliminating BQ chewing may prevent 51.6% of HNCs, 62.6% of oral cancers, and 41.3% of pharyngeal cancers in Taiwan.
  
  
  CONCLUSIONS
  Our results supported the positive association between BQ and HNC. BQ cessation is effective in reducing HNC risk and should be encouraged. Because BQ cessation may not reduce the HNC risk to the level of non-BQ chewers, it is important to prevent the initiation of BQ chewing.
authors: Department of Radiation Oncology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Yuan-Hua
authors: YH
authors: Wu
authors: Division of Hematology/Oncology, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Chia-Jui
authors: CJ
authors: Yen
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Jenn-Ren
authors: JR
authors: Hsiao
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Chun-Yen
authors: CY
authors: Ou
authors: Department of Stomatology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Jehn-Shyun
authors: JS
authors: Huang
authors: Department of Stomatology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Tung-Yiu
authors: TY
authors: Wong
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Sen-Tien
authors: ST
authors: Tsai
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Cheng-Chih
authors: CC
authors: Huang
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Wei-Ting
authors: WT
authors: Lee
authors: Department of Stomatology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Ken-Chung
authors: KC
authors: Chen
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Sheen-Yie
authors: SY
authors: Fang
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Jiunn-Liang
authors: JL
authors: Wu
authors: Department of Radiation Oncology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Wei-Ting
authors: WT
authors: Hsueh
authors: Department of Radiation Oncology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Forn-Chia
authors: FC
authors: Lin
authors: Department of Radiation Oncology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Ming-Wei
authors: MW
authors: Yang
authors: Division of Hematology/Oncology, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.|National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan.
authors: Jang-Yang
authors: JY
authors: Chang
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Hsiao-Chen
authors: HC
authors: Liao
authors: Division of Hematology/Oncology, Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Shang-Yin
authors: SY
authors: Wu
authors: Department of Nursing, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Chen-Lin
authors: CL
authors: Lin
authors: National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan.
authors: Yi-Hui
authors: YH
authors: Wang
authors: National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan.
authors: Ya-Ling
authors: YL
authors: Weng
authors: National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan.
authors: Han-Chien
authors: HC
authors: Yang
authors: Department of Otolaryngology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors: Yu-Shan
authors: YS
authors: Chen
authors: National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan.
authors: Jeffrey S
authors: http://orcid.org/0000-0002-8409-909X
authors: JS
authors: Chang
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000453:epidemiology*; D016022:Case-Control Studies; D006258:Head and Neck Neoplasms / Q000453:epidemiology*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008409:Mastication; D008875:Middle Aged; D031721:Piper betle / Q000009:adverse effects*; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology*; D000077195:Squamous Cell Carcinoma of Head and Neck; D013624:Taiwan / Q000453:epidemiology