Betel quid chewing and the risk of oral and oropharyngeal cancers: A meta‐analysis with implications for cancer control

Abstract

We conducted a random-effects meta-analysis of 50 publications assessing the relationship between oral/oropharyngeal cancer and chewing betel quid, with (BQ1T) or without added tobacco (BQ-T), a common practice in many parts of Asia and globally among Asian immigrants. Exposure-response, by daily amount and years of BQ chewed, was assessed using spline models. Attributable fractions (PAF%) were calculated to estimate the public health impact if BQ were no longer chewed. The meta-relative risk (mRR) for oral/oropharyngeal cancer in the Indian subcontinent was 2.56 (95%CI, 2.00-3.28; 15 studies) for BQ-T and 7.74 (95%CI, 5.38-11.13; 31 studies) for BQ1T; in Taiwan, China, the mRR for BQ-T was 10.98 (95%CI, 4.86-24.84; 13 studies). Restricting to studies that adjusted for tobacco and alcohol use had only a small effect on the risk estimates. For BQ1T in the Indian subcontinent, the mRR was much higher in women (mRR, 14.56; 95%CI,) than in men. Exposure-response analyses showed that the risk of oral/oropharyngeal cancer increased with increasing daily amount and duration (years) of chewing BQ in India and Taiwan, China. Roughly half of oral cancers in these countries could be prevented if BQ were no longer chewed (PAF% 5 53.7% for BQ-T in Taiwan, China; PAF% 5 49.5% for BQ1T in India). We demonstrate that betel quid chewing, with or without added tobacco, increases the risk of oral/oropharyngeal cancer in an exposure-dependent manner, independently of tobacco and alcohol use. Further work is needed to explain the higher risks associated with chewing BQ-T

Smokeless Tobacco and Oral Cancer in South Asia: A Systematic Review with Meta-Analysis

“…Users of betel quid with tobacco have a sevenfold higher risk for developing oral cancer as compared to nonchewers, OR 7.1 [4.5–11.1]. This finding is consistent with findings from the earlier reviews [15, 16]. Similarly, people using other forms of SLT than betel quid with tobacco have an almost five-time higher risk of developing oral cancer as compared to nonchewers, OR 4.7 [3.1–7.1].…”

A Comprehensive Analysis on the Association between Tobacco-Free Betel Quid and Risk of Head and Neck Cancer in Taiwanese Men

“…The only other Taiwanese study that examined the non-linear relationship between BQ and HNC also reported dose-response curves similar to ours, with risk of oral cancer and pharyngeal cancer increasing sharply from 0 to 15 BQs per day and attenuated after 15 BQs per day [4]. In a meta-analysis by Guha et al ., a dose-response curve similar to ours was observed for studies from India for number of BQ per day and years of BQ chewing, whereas the meta-analysis of studies from Taiwan showed a linear positive association between number of BQ per day and HNC [7]. A limitation of the meta-analysis is that the spline models were built using the reported relative risks based on categorized BQ exposures and not the original data points.…”

“…Although BQ is an established risk factor for HNC, current literature has several insufficiencies: 1) most studies did not examine the different types of BQ; 2) many studies did not adjust for potential confounders, including alcohol and cigarette; 3) only a few studies examined the association between BQ and HNC by sites; 4) inadequate data on dose-response; and 5) lack of data on HNC risk after BQ cessation [7]. We conducted a comprehensive analysis to address these insufficiencies.…”

Clinicopathological characteristics of oral squamous cell carcinoma in Northern Norway: a retrospective study

“…For persons who smoke and drink alcohol daily, the odds ratio are reported to be as high as 35 [12,13]. In Southern Asia the chewing of betel quid and areca nuts explains the high incidence [14,15]. The exposure to various risk factors also has impact on the primary site of OSCC, betel quid and areca nut chewing mainly disposing for tumours arising in the buccal mucosa, while cigarette smoking and alcohol are disposing for tumours in the floor of mouth [1,12,16-18].…”