Table 1.
Studies Reporting Risk of Oral Cancer in Betel Quid Chewers Without Tobacco (Since Last IARC Evaluation in 2014).
| Reference | Country or Region | Study Design | Exposure | Odds Ratio (95% CI) |
|---|---|---|---|---|
| Chen et al. (2009) | Taiwan | Case-control study: 174 oral cancer cases and 347 controls | Chewer vs. nonchewer | 20.1 (12.6 to 32.0) |
| Chung et al. (2009) | Taiwan | Case-control study: 160 oral cancer cases and 218 controls | Chewer vs. nonchewer | 45.4 (21.1 to 97.5) |
| Kietthubthew et al. (2010) | Thailand | Case-control study: 107 oral cancer cases and 157 controls. | Betel quid chewer vs. nonchewer | 1.9 (1.1 to 3.1) |
| Wang et al. (2010) | Taiwan | Case-control study: 294 oral cancer cases and 333 controls | Chewer vs. nonchewer | 42.8 (26.9 to 67.9) |
| Chang et al. (2011) | Taiwan | Case-cohort study: 285 oral cancer cases and 13,321 subjects | Betel quid chewing vs. nonchewer | 9.2 (2.8 to 30.7) |
| Chen et al. (2011a) | Taiwan | Case-control study: 216 oral cancer cases and 344 controls | Chewer vs. nonchewer | 20.6 (13.3 to 31.9) a |
| Chen et al. (2011b) | Taiwan | Case-control study: 247 oral cancer cases and 338 controls | Chewer vs. nonchewer | 17.3 (9.0 to 33.2) |
| Chung et al. (2011) | Taiwan | Case-control study: 415 oral cancer cases and 341 controls | Chewer vs. nonchewer | 12.4 (8.8 to 17.4) |
| Lee et al. (2011) | South and East Asia | Cohort study: 1,522 subjects | Chewer vs. nonchewer | 1.6 (1.3 to 2.0) b |
| Lin et al. (2011) | Taiwan | Cohort study: 10,657 subjects | Smoking, alcohol consumption, and betel quid chewing vs. none | 34.8 (25.9 to 46.8) |
| Yuan et al. (2011) | Taiwan | Case-control study: 101 oral cancer cases and 104 controls | Chewer vs. nonchewer | 16.0 (7.7 to 33.1) |
| Zavras et al. (2011) | Taiwan | Case-control study: 240 oral cancer cases and 347 controls | Chewer vs. nonchewer | 19.9 (11.5 to 34.3) |
| Chen et al. (2012) | Taiwan | Case-control study: 444 oral cancer cases and 426 controls | Chewer vs. nonchewer | 13.9 (10.0 to 19.3) |
| Chien et al. (2012) | Taiwan | Case-control study: 462 oral cancer cases and 519 controls | Chewer vs. nonchewer | 15.2 (11.2 to 20.8) |
| Helen-Ng et al. (2012) | Malaysia | Case-control study: 153 oral cancer cases and 153 controls | Chewer vs. nonchewer | 2.2 (1.3 to 3.8) |
| Lee et al. (2012) | South, Southeast, and East Asia | Case-control study: 810 oral cancer cases and 2,250 controls | Chewer vs. nonchewer | 16.2 (12.1 to 21.7) |
| Lin et al. (2012a) | Taiwan | Case-control study: 462 oral cancer cases and 520 controls | Chewer vs. nonchewer | 15.3 (11.2 to 20.9) |
| Lin et al. (2012b) | Taiwan | Case-control study: 195 oral cancer cases and 81 controls | Chewer vs. nonchewer | 21.8 (10.6 to 44.8) |
| Liu et al. (2012) | Taiwan | Case-control study: 270 oral cancer cases and 350 controls | Chewer vs. nonchewer | 21.0 (13.9 to 31.7) |
| Loyha et al. (2012) | Thailand | Case-control study: 104 oral cancer cases and 104 controls | Chewer vs. nonchewer | 9.0 (3.8 to 21.2) |
| Madani et al. (2012) | India | Case-control study: 350 oral cancer cases and 350 controls | Chewer vs. nonchewer | 6.6 (3.0 to 14.8) |
| Zavras et al. (2012) | Taiwan | Case-control study: 239 oral cancer cases and 336 controls | Chewer vs. nonchewer | 20.1 (13.1 to 30.8) |
| Chien et al. (2013) | Taiwan | Case-control study: 470 oral cancer cases and 426 controls | Chewer vs. nonchewer | 14.0 (10.1 to 19.3) |
| Tsai et al. (2014) | Taiwan | Case-control study: 788 oral cancer cases and 956 controls | Chewer vs. nonchewer | 4.6 (3.7 to 5.8) |
| Wong et al. (2014) | Taiwan | Case-control study: 50 oral cancer cases and 50 controls | Chewer vs. nonchewer | 1.3 (0.5 to 3.4) |
| Yang et al. (2014a) | Taiwan | Case-control study: 463 oral cancer cases and 623 controls | Chewer vs. nonchewer | 8.1 (5.5 to 11.8) |
| Yang et al. (2014b) | Taiwan | Case-control study: 191 oral cancer cases and 100 controls | Chewer vs. nonchewer | 14.7 (8.0 to 26.9) |
| Lee et al. (2015) | Taiwan | Case-control study: 507 oral cancer cases and 717 controls | Chewer vs. nonchewer | 35.1 (25.6 to 48.3) |
| Chou et al. (2014) | Taiwan | Case-control study: 595 oral cancer cases and 561 controls | Chewer vs. nonchewer | 16.5 (12.3 to 22.1) |
| Lin et al. (2015) | Taiwan | Case-control study: 618 oral cancer cases and 560 controls | Chewer vs. nonchewer | 17.1 (12.8 to 23.0) |
| Su et al. (2015) | Taiwan | Case-control study: 747 oral cancer cases and 1,200 controls | Chewer vs. nonchewer | 20.7 (16.4 to 26.2) |
| Chou et al. (2017a) | Taiwan | Case-control study: 876 oral cancer cases and 1,200 controls | Chewer vs. nonchewer | 20.2 (16.1 to 25.2) |
| Chou et al. (2017b) | Taiwan | Case-control study: 955 oral cancer cases and 1,191 controls | Chewer vs. nonchewer | 20.3 (16.3 to 25.4) |
| Chuang et al. (2017) | Taiwan | Cohort study: 2,334,299 subjects | Betel quid chewing without/with smoking vs. smoking only | 2.8 (2.6 to 3.0) a |
| Chung et al. (2017a) | Taiwan | Case-control study: 447 oral cancer cases and 580 controls | Betel quid chewing vs. none. | 26.7 (16.7 to 42.8) |
| Chung et al. (2017b) | Taiwan | Case-control study: 410 oral cancer cases and 282 controls | Chewer vs. nonchewer | 28.5 (19.2 to 42.3) |
| Tsai et al. (2018), Shih et al. (2018) | Taiwan | Case-control study: 788 oral cancer cases and 956 controls | Chewer vs. nonchewer | 5.9 (4.7 to 7.4) |
| Su et al. (2018) | Taiwan | Case-control study: 1,044 oral cancer cases and 1,200 controls | Chewer vs. nonchewer | 16.5 (13.4 to 20.3) |
| Wu et al. (2018) | Taiwan | Cohort study: 310 subjects (malignant transformation for oral verrucous hyperplasia) | Betel quid chewing: (1) 10 to 20 and (2) >20 quids/d vs. <10 | (1) 1.4 (0.8 to 2.5) and (2) 2.0 (1.3 to 4.0) b |
| Yang et al. (2018) | Taiwan | Case-control study: 935 oral cancer cases and 1,200 controls | Chewer vs. nonchewer | 19.7 (15.8 to 24.6) |
| Huang et al. (2019) | Taiwan | Case-control study: 282 oral cancer cases and 324 controls | Chewer vs. nonchewer | 37.0 (17.4 to 85.6) |
| Chen et al. (2019) | Taiwan | Case-control study: 242 oral cancer cases and 264 controls | Chewer vs. nonchewer | 1.3 (0.8 to 2.2) |
| Chung et al. (2019) | Taiwan | Case-control study: 360 oral cancer cases and 486 controls | Chewer vs. nonchewer | 26.8 (18.6 to 38.8) |
| Lin et al. (2019) | Taiwan | Case-control study: 741 oral cancer cases and 462 controls | Chewer vs. nonchewer | 15.9 (11.9 to 21.3) |
| Su et al. (2019) | Taiwan | Cohort study: 5,743 subjects | Betel quid chewing without smoking vs. smoking only | 1.2 (1.0 to 1.5) |
| Yen et al. (2019) | Taiwan | Cohort study: 235,234 subjects | Betel quid chewing with/without smoking vs. smoking only | 2.2 (1.8 to 2.7) b |
| Shih et al. (2020), Wu et al. (2021) | Taiwan | Case-control study: 958 oral cancer cases and 958 controls | Chewer vs. nonchewer | 3.7 (3.0 to 4.5) |
| Yeh et al. (2020) | Taiwan | Case-control study: 1,196 oral cancer cases and 1,200 controls | Chewer vs. nonchewer | 13.7 (11.2 to 16.7) |
| Hu et al. (2020) | Mainland China | Case-control study: 304 cases and 304 controls | Chewer vs. nonchewer | 5.4 (3.3 to 8.8) |
| Lin et al. (2020) | Mainland China | Cohort study: 915 subjects: (Metachronous multiple primary oral cancer) | Betel quid chewing without smoking | 11.1 (9.23 to 13.3) |
| Chen et al. (2021) | Taiwan | Case-control study: 297 oral cancer cases and 193 controls | Chewer vs. nonchewer | 13.3 (8.5 to 20.8) |
For reference list, see Appendix.
IARC, International Agency for Research on Cancer.
a
Values are presented as relative risk (95% CI).
b
Values are presented as hazard ratio (95% CI).