| [ Summary ] |
The effects of cigarette smoking or alcohol consumption on the risks for gastric cancer have not yet been clarified. In this study, we investigated this relationship, considering the anatomic subsite and histologic type of gastric cancer. A total of 19,657 men (aged 40 to 59 years at baseline), who responded to the baseline questionnaire and reported no serious illness at that time, were followed for 10 years, from January 1990 to December 1999. Gastric cancer was confirmed histologically in 293 of these men. Smoking was associated with an increased risk of the differentiated type of distal gastric cancer; when compared with the group who never smoked; the adjusted rate ratios (RRs) for gastric cancer for past and current smokers were 2.0 [95% confidence interval (CI) 1.1 to 3.7] and 2.1 (1.2 to 3.6), respectively. No association was observed between cigarette smoking and the risk of the undifferentiated type of distal gastric cancer except for a suggestive association with cardia cancer. For alcohol consumption, an elevated risk was suggested only for cardia cancer of all histologic types, although the relationship failed to reach any significant conclusions. Among those who drank alcohol at least once per week, RRs for ethanol intake of 0 to 161.0 g/week, 162.0 to 322.0 g/week, and 322.5+ g/week compared with those who drank 0 to 3 times/month were 2.5 (95% CI 0.7 to 9.5), 3.3 (0.9 to 11.6), and 3.0 (0.8 to 11.1), respectively (p for trend=0.66). In conclusion, the results confirmed that smoking is related to gastric cancer of the differentiated type. Further studies with more cases are needed to detect a positive association between cigarette smoking or alcohol consumption and cardia cancer. |