Does tobacco smoke cause breast cancer?

摘要

More than 1 billion people currently smoke tobacco [1], and tobacco consumption is the leading cause of cancer worldwide. Even more people, especially women in developing countries, continue to be exposed to second-hand smoke. Consequently, efforts to determine whether tobacco smoke affects breast cancer risk, and if so, the nature and strength of the relationships with active and passive smoking, have important public health as well as scientific implications. Some researchers have posited that tobacco smoke increases breast cancer risk as much or more so among women who are exposed passively to tobacco smoke as in those who smoke actively. If this were true, then reductions in active and passive smoking would be among the most important interventions for the prevention of breast cancer, in addition to their numerous other health benefits. However, to date, no scientific consensus has been reached on these issues, despite more than 20 years of debate and over 150 epidemiological studies [1-3].