Coffee consumption not associated with risk of pancreas cancer in Finland

Coffee consumption has been brought to focus as a possible risk factor for pancreas cancer. After having reviewed the available evidence, an International Agency for Research on Cancer working group concluded in 1991 that the evidence in humans that coffee drinking is carcinogenic in the pancreas is "inadequate," since the available data were considered suggestive of a weak relationship with high levels of coffee consumption, but the possibility that this was due to bias or confounding was judged tenable.

The association between coffee consumption and pancreas cancer risk was examined in a case-referent study in Finland. Data on coffee consumption 20 years prior to the diagnosis of cancer were obtained from the next of kin of 662 cases of pancreas cancer and 1,770 referent (stomach, colon, and rectum) cancers. The results were expressed as crude and age-, gender-, and tobacco smoking-adjusted odds ratios and 95% confidence intervals for three daily coffee dose categories 20 years prior to cancer diagnosis.

The data failed to demonstrate any association between coffee consumption and risk for pancreas cancer. The crude odds ratios varied between 0.7 (95% confidence interval 0.3-1.5) and 1.3 (0.7-2.6), the adjusted ones between 0.5 (0.2-1.2) and 1.1 (0.6-2.1) in the different daily dose categories of coffee and between contrasts with the three referent cancers. The highest odds ratios were associated with the contrast between pancreas and colon cancer, the lowest between pancreas and rectum cancer. Adjustment for gender, age, and tobacco smoking slightly decreased the values of the odds ratios. The power of the study was low, however, to detect possible weak increases associated with coffee consumption.

The results are unlikely to be negatively biased, and are compatible with the majority of epidemiologic results advanced, suggesting no positive association between coffee consumption and the risk of pancreas cancer.