Last year, hundreds of thousands of women in the United States had breast implants. Breast implants can enhance or reshape a woman’s breasts, or reconstruct them after mastectomy to treat breast cancer . Although breast implants have periodically been linked to breast and other cancers, epidemiologic studies have not consistently shown any association between the two.

Now, in the longest follow-up study of breast implants to date, researchers report that breast implants did not increase the risk of cancer overall, and were actually associated with a decreased the risk of breast cancer. These findings were published in the April 19, 2006 Journal of the National Cancer Institute .

About the Study

The researchers obtained the medical records of 3,486 Swedish women who had undergone breast implantation, and followed them for an average of 18.4 years. (The women in this study had cosmetic breast implants, implying that they were not used for reconstruction after mastectomy.) The researchers compared the incidence of various cancers in these women during the study’s follow-up period to the expected incidence of the same cancers in women from the general population.

One-hundred and eighty women in this study developed cancer during the follow-up period, compared to 193 cancers that were expected in the general population. Therefore, breast implants did not increase the risk of cancer overall. Women with breast implants were at a decreased risk for breast cancer compared to women in the general population (53 cases, versus 71.9 expected). Women with breast implants did have a significantly increased risk of lung cancer compared to women in the general population. (However, the women in this study were 2.8 times as likely to smoke as women in the general population, which put them at higher risk for lung cancer.)

How Does This Affect You?

This study demonstrated no association between breast implants and increased risk of breast cancer or cancer overall.

That being said, breast implantation is a surgical procedure, and like all surgery, it has inherent risks. Once the implant is in place, some women experience a hardening of breast tissue around the implant, and implants can leak or rupture. In addition, breast implants have been linked to autoimmune and connective tissue diseases such as lupus and scleroderma , although this association is controversial and far from certain.

If you are considering cosmetic surgery, discuss the potential risks with your physician, then carefully weigh the risks and benefits. You will be unlikely to increase your risk of breast cancer if you decide to proceed with surgery.