National Cancer Institute
National Institute of Health

Key Points

• The authors of the study found that antibiotic use was associated with an increased risk of breast cancer. The more antibiotics the women in the study had used, the higher their risk of breast cancer. (Question 1)
• These results do not mean that antibiotics cause cancer, only that there is an association between the two. (Question 2)
• Breast cancer is the second leading cause of cancer deaths among women in the United States. An estimated 40,110 women will die of the disease this year. (Question 9)
• Antibiotics are used extensively in this country and in many parts of the world. They can have substantial benefits when used to treat bacterial infections. Antibiotics also are overused in many parts of the world, contributing to the growth of antibiotic resistance. This study provides more reason to use antibiotics wisely. (Questions 9, 12 and 13)
• More studies must be done to understand what causes the increased risk of breast cancer with antibiotic use. (Questions 2, 7, 8, 14)

Full Story:  http://www.cancer.gov/newscenter/newsfromnci/2004/antibioticsQA