Tobacco and Public Health - TCSC Indonesia

Chapter 29
Tobacco smoking and cancer of
the breast
Dimitrios Trichopoulos
and Areti Lagiou
Tobacco smoking is the most important human carcinogen, and breast cancer is, at
least in the developed world, the type of cancer that causes more deaths among women
(Lagiou and Adami 2002). If tobacco smoking were found to be a factor that increases
the risk of breast cancer, the implications would extend beyond the potential prevention
of a number of breast cancer cases, because of the emotional impact that this form
of cancer has. The evidence, however, has been unusually puzzling.
Biologic considerations
It has been reported that active smoking may increase (Lash and Aschengrau 1999;
Johnson et al. 2000), reduce (Vessey et al. 1983), or be unrelated to (MacMahon 1990;
Egan et al. 2002) the risk of breast cancer. More recently, it has been indicated that
passive smoking may increase the risk of this disease (Morabia et al. 1996). Various
biological plausibility arguments have been invoked in support of each of the various
possibilities:
◆ Tobacco smoking may reduce the risk of breast cancer. Tobacco smoking has established
anti-estrogenic effects (MacMahon et al. 1982; Baron 1984; Michnovicz et al. 1986)
and estrogens are important determinants of breast cancer risk (Hankinson and
Hunter 2002). The anti-estrogenicity of tobacco smoking is manifested in several
associations with estrogen-dependent diseases or conditions, including associations
with earlier menopause (Cooper et al. 1999), osteoporosis (Hopper and Seeman
1994), and endometrial cancer (Terry et al. 2002). An inverse association between
tobacco smoking and breast cancer has been reported for men (Casagrande et al.
1988; Petridou et al. 2000) among whom tobacco smoking also has anti-estrogenic
effects (Michnovicz and Fishman 1990).
◆ Tobacco smoking may increase the risk of breast cancer. Tobacco smoke is an
established human carcinogen (IARC Monographs 1986) and causes cancer in
several non-respiratory sites, including pancreas (Lowenfels and Maisonneuve
2002) and liver (Kuper et al. 2000). It contains several fat-soluble compounds with