Blood iron, glutathione, and micronutrient levels and the risk of oral cancer.

The risk of oral cavity cancer was determined in relation to serological levels of iron; vitamins A, B2, C, E; zinc; thiamin; and glutathione (GSH). The study included 65 hospitalized patients with oral cancer and 85 matched controls. In comparing the highest to the lowest tertiles, the risk was odds ratio (OR) = 0.

Comparison between hospitalized and screening controls in studies assessing breast cancer risk.

Background: In case-control studies, selection of an appropriate group of controls is a critical step which may affect the outcome of the analysis.

Methods: We studied the differences in reproductive, lifestyle, and anthropometric variables between controls from a hospital-based study and controls from a screening clinic. Odds ratios for breast cancer were calculated using the two types of controls, and the impact on the resulting odds ratio was studied.

Smoking and lung cancer risk in American and Japanese men: an international case-control study.

Rates of lung cancer in American men have greatly exceeded those in Japanese men for several decades despite the higher smoking prevalence in Japanese men. It is not known whether the relative risk of lung cancer associated with cigarette smoking is lower in Japanese men than American men and whether these risks vary by the amount and duration of smoking. To estimate smoking-specific relative risks for lung cancer in men, a multicentric case-control study was carried out in New York City, Washington, DC, and Nagoya, Japan from 1992 to 1998.