Federal health officials warned Wednesday that breast implants might increase the risk of developing a rare form of lymphoma.
The Food and Drug Administration announced it had detected a possible association between saline and silicone gel-filled breast implants and anaplastic large cell lymphoma (ALCL), a cancer of the immune system.
Most women with implants do not have to have them removed or take any other steps beyond the routine monitoring of their health because of the concerns, official said. But women with implants who develop any unusual problems, such as swelling or pain around the implant, should immediately seek medical care, and any women considering implants should be informed of the possible risk, they said.
"Although very rare, the FDA believes women with breast implants may have a small increased risk of developing ALCL," said William Maisel, the FDA's chief scientist.
Worldwide, between 5 million and 10 million women have breast implants, including many women who received the devices as part of reconstructive surgery following breast cancer. So far, only about 60 cases of the disease have been identified in women with implants, Maisel said.
Because of the small number of cases in women with implants so far, the agency urged doctors to report any additional cases immediately. The agency was working with the American Society of Plastic Surgeons and others to set up a breast implant patient registry to better understand any link between implants and the cancer.
How implants may cause the disease remains unclear, but silicone has been found in some cells surrounding the implants, indicating the cancer could be caused by the simulation of immune system cells known as T cells, Maisel said.
The announcement was prompted by a review of scientific literature published between January 1997 and May 2010 that identified 34 cases and "information from other international regulators, scientists and breast implant manufacturers" that found about 26 more, the FDA said.
In women without breast implants, ALCL is diagnosed in about one out of 500,000 in the United States each year, the FDA said.
The warning is the latest safety concern to arise related to breast implants. Silicone breast implants were banned for most U.S. women in 1992 after concerns emerged they may be linked to a variety of health problems, including cancer and rheumatoid arthritis. But after subsequent studies appeared to exonerate the implants, the FDA allowed sales to resume, despite protests from some consumer advocates.
Breast implants are sold by two companies -- Allergan Inc. and Johnson & Johnson's Mentor Corp. Maisel said that the firms were behind schedule in conducting safety studies they were required to perform when implants returned to the market.
"Today's announcement is frightening for American consumers - not only because these implants may be dangerous, but also because it exposes the inadequacies of the process at FDA for requiring post market studies of medical devices," said Rep. Rosa L. DeLauro (D-Conn.).