Obesity, alcohol, and tobacco as risk factors for cancers of the esophagus and gastric cardia: adenocarcinoma versus squamous cell carcinoma.

Adenocarcinomas of the esophagus and gastric cardia were once rare. However, for unknown reasons, their incidence has been increasing rapidly over the past 15 years in the United States and parts of Western Europe. In contrast, the incidence of esophageal squamous cell carcinomas has remained relatively constant. To investigate possible reasons for these diverging incidence rates we analyzed data from two population-based case-control studies of cancers of the esophagus and gastric cardia that were conducted among male and female residents of western Washington between 1983 and 1990. Information on body mass index, cigarette use, alcohol intake, and other possible risk factors was collected via personal interviews with 404 cases or their next of kin (including 298 adenocarcinomas and 106 squamous cell carcinomas) and 724 controls identified by random digit dialing. Use of alcohol and cigarettes were significant risk factors for both histological types. The increase in risk for current smokers of 80 or more pack-years compared to nonsmokers was substantially higher for squamous cell cancer [odds ratio (OR) = 16.9; 95% confidence interval (CI) = 4.1-69.1] than for adenocarcinoma (OR = 3.4; 95% CI = 1.4-8.0), as was the increase for persons who typically drank 21 or more drinks/week compared to those who drank <7/week (OR = 9.5; 95% CI = 4.1-22.3 versus OR = 1.8; 95% CI = 1.1-3.1). For squamous cell carcinoma, body mass index was inversely associated with risk, whereas for adenocarcinoma, the highest risk was observed among persons who were in the highest decile of body mass index (OR = 1.9; 95% CI = 1.1-3.2).(ABSTRACT TRUNCATED AT 250 WORDS)