The committee concludes, from its assessment of the epidemiologic literature, that there is inadequate/insufficient evidence to determine whether an association exists between exposure to fuels or combustion products and esophageal cancer.
This review focuses on gastric cancer (commonly known as stomach cancer) (ICD-9 151). Risk factors for stomach cancers are increasing age, sex, ethnicity, family history, dietary habits, and tobacco and alcohol use (ACS 2004q, 2004w). Heliobacter pylori infection is also a known cause of stomach cancer.
In 2000, there were 8.0 new cases of stomach cancer per 100,000 people (11.6 among men and 5.3 among women) and 4.6 deaths per 100,000 (6.4 among men and 3.2 among women) in the United States (Ries et al. 2004).
Table 4.7 presents the most relevant findings reviewed by the committee in drawing its conclusion on the possibility of an association between exposure to fuels and stomach cancer.
Two cohort studies assessed the risk of combined esophageal and stomach cancer posed by exposure to fuels (Hanis et al. 1979; Ritz 1999). The results are presented in the previous section on esophageal cancer. No increased risk of stomach cancer was found in a nationwide survey of gasoline-station attendants in Italy (Lagorio et al. 1994). Amoco Oil Company employees in 1970–1980 who worked in operations were at increased risk for stomach cancer, with an SMR of 2.06 (Nelson et al. 1987), but those working in administration (and presumably were not exposed to petroleum products) had an SMR of 1.80.
A case-control study of 3,726 cases of cancer in men in 19 Montreal hospitals was conducted to determine whether there was an association exists between exposure to fuels and various cancers, including stomach cancer (Siemiatycki et al. 1987a). Exposure was assessed with an industrial-hygiene assessment of exposure based on occupational history. The authors presented 90% confidence intervals and reported borderline increased risks for participants with automotive-gasoline exposure (OR 1.5, 90% CI 1.2–1.9). The risk of stomach cancer also was increased after exposure to kerosene (OR 1.7, 90% CI 1.2–2.3).
Table 4.8 presents the most relevant findings reviewed by the committee in drawing its conclusion on the possibility of an association between exposure to combustion products and stomach cancer.