Women who opt for silicon breast implants have an increased risk of developing a rare form of lymphoma. About 0.1 to 0.3 per 100,000 women with implants each year are susceptible to the disease, according to the Dutch authors of a study published in the Nov. 5 issue of the Journal of the American Medical Association.

Silicone breast implants have been a centre of controversy for over a decade now. The U.S. Food and Drug Administration lifted a 14-year ban on their commercial use in 2006. Only two companies - Allergan Inc., of Irvine, Calif., and Mentor Corp, of Santa Barbara, Calif. were allowed, to market the implants to all women aged 22 and older.

In 1992, the implants had been removed from the market due to suspicions that they might cause cancer or certain autoimmune diseases. It was also suspected that the implants might interfere with the accuracy of breast cancer screening. They could also cause ruptures which could trigger other health problems.

The link between silicone implants and lymphoma was studied by Dr. Daphne de Jong, from The Netherlands Cancer Institute, Amsterdam and his colleagues. They studied two patients who had ALCL in the fibrous capsule surrounding their silicone breast implants. 

"These findings must be considered preliminary and hypothesis-generating and are not strong enough to definitively conclude that breast implants predispose women to non-Hodgkin lymphoma," Dr. Andrew M. Evens and Dr. Brian C.-H. Chiu, from Northwestern University, Chicago, write in an accompanying editorial.

"Doctors should be aware of this . . . but it's not something women should worry about," said Dr. Mitchell Smith, head of the lymphoma service at Fox Chase Cancer Center in Philadelphia. "People with implants have a one in many hundreds of thousands or one in a million chance of developing this cancer."