Among 104 cases of squamous-cell oesophageal carcinoma patients and 277 con
trols in Taiwan, after adjusting for cigarette smoking, alcohol consumption
, and other confounders, we found that subjects who chewed from 1 to 495 be
tel-year and more than 495 betel-years (about 20 betel quid per day for 20
years) had 3.6-fold (95% CI = 1.3-10.1) and 9.2-fold risk (95% CI = 1.8-46.
7), respectively, of developing oesophageal cancer, compared to those who d
id not chew betel. (C) 2001 Cancer Research Campaign.