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Past, present smoking ups breast cancer risk

A woman is seen smoking a cigarette in this file photo.

January 25, 2011 12:00:00 AM PST
A new study found that smoking may slightly increase the risk of breast cancer.

Researchers used the records of the long-running Nurses' Health Study. Scientists say any history of smoking increased a woman's chance of breast cancer by 6 percent.

Exposure to secondhand smoke did not appear to increase a woman's risk of breast cancer.

The study is in Tuesday's issue of Archives of Internal Medicine.