Smoking and Breast Cancer

Is smoking related to breast cancer risk?

Many studies have shown inconclusive and conflicting results regarding the association of smoking with breast cancer. But newer studies have challenged this conclusion and suggested a connection between smoking and an increased risk of breast cancer

Studies have yet to conclusively prove a link between tobacco smoke and breast cancer, but evidence is piling up.

Is active smoking related to breast cancer risk?

It is biologically possible that active cigarette smoking or passive smoking can increase the breast cancer risk. There is direct documentation that breasts are exposed to chemicals within tobacco smoke in active smokers. Study of the fluid in the ducts of the breast of smoking women has shown the presence carcinogens and chemicals at higher concentrations. So this shows that smoking can increase the risk of breast cancer.

Many researches show women who smoke have a much higher risk of developing breast cancer compared with women who have never smoked.

  • Recent studies say that among current smokers, the risk of breast cancer is significantly higher than those who started smoking before 20 years.
  • Recent studies say that current smoking is associated with a higher risk of breast cancer among women with no family history of breast cancer, but not among those with a family history of the disease.
  • Active smoking is linked to aggressive, hormone receptor-negative (HR-) type breast cancer.
    Smoking may promote the spread of breast cancer to lungs.


Is passive smoking related to breast cancer risk?

Most, but not all, studies that compared women who were passively exposed to tobacco smoke to women with no exposure to tobacco smoke reported an association of passive smoking with an increased risk of breast cancer.

A survey of studies by the Public Health Agency of Ottawa, Ontario Canada, even showed that secondhand smoke increases risk of developing premenopausal breast cancer by 14 to 119%, depending on the amount of exposure.

  • Studies say that long-term exposure to passive smoking is associated with an overall increased breast cancer risk of 27 percent in life-long nonsmokers.

Early age smoking and breast cancer

Most studies reported exposure to tobacco smoke at a young age either by smoking or by passive smoking may increase the risk of breast cancer at the later age.

  • Other studies reported a small increase in breast cancer risk associated with starting smoking under age 17.
  • Secondhand (passive) smoke may increase risk in younger, premenopausal women.
  • Teens who smoke are more likely to develop breast cancer before menopause.


Adult Women, Smoking, and Breast Cancer

  • Premenopausal women who smoke have an increased risk of breast cancer as well as lung cancer. Women who stop smoking can decrease their risk of breast cancer to average that of nonsmokers’ after 10 years.
  • After menopause, when estrogen levels decline, an active or long-term female smoker who started smoking before age 65 and before her first child was born has a 30 to 40% increased risk of breast cancer.
  • If a postmenopausal woman smoked for 20 years or more and used hormone replacement therapy (HRT), which boosts estrogen levels, her risk is 50% greater than average.
  • Older women who have smoked for 11 years or more may face 30% to 40 % increased risk of developing breast cancer as compared to women who’ve never smoked.

Though the association of smoking and breast cancer is controversial but many recent studies say it as a significant and independent risk factor for breast cancer.