Active smoking appears to play a larger role in the development of breast cancer than previously thought, according to a study in the January 7 issue of the Journal of the National Cancer Institute.
Tobacco smoke contains a number of human carcinogens, and metabolites of cigarette smoke have been found in the breast fluid of smokers. However, studies examining the association between tobacco smoke and breast cancer risk have yielded inconsistent results. Many studies have not been able to independently assess the contributions of the timing of exposure, age of diagnosis, or genetic susceptibilities to the overall risk of breast cancer. In addition, many of these studies did not consider passive smoking exposures, or exposure to secondhand smoke, among nonsmokers.
Cancer Spectrum: Arnold, pp. 1
