April 13, 2005 - An FDA advisory panel recommended Wednesday that silicone implants be brought back to the U.S. market for breast augmentation, 13 years after the agency enacted a partial ban on their use because of safety concerns.
Experts backed one company's bid to sell the implantsbecause of concerns about durability and safety.
The panel supported the application from implant maker Mentor by a 7 to 2 vote. But the panel recommended that strict conditions be imposed on the manufacturer, including close patient tracking and informed consent. The panel also called for certification of physicians implanting the silicone-filled devices.
A final FDA approval would give the company access to the more than 340,000 women expected to seek cosmetic breast enlargement surgery this year. The agency ordered the implants off the broad market in 1992, restricting them to women seeking reconstructive surgery following a mastectomy.
Several panel members said they based their support Wednesday on evidence that Mentor's implant appeared less likely to rupture than a similar implant produced by Inamed, a rival firm. Inamed's application for producing implants was rejected by the panel on Tuesday.
But experts also expressed unease with thewhich for years have sparked controversy because of suspicions that they could leak and cause autoimmune diseases and other illnesses.
Mentor officials presented a study showing that their implants ruptured in 1.4% of all cases (enlargements and reconstruction) within three years after surgery, representing about one in every 72 women who used them. The implants broke within three years in one in every 200 women who got them specifically for cosmetic breast enlargement, the company said.
Officials said none of the ruptures resulted in adverse health problems or disease, except for some breast pain and altered shape in a few cases.
The company also presented a small British study suggesting that the implants could be expected to rupture in 5.4% of women within nine years, a much lower rate than the 14% rupture rate projected by Inamed.
On Tuesday, experts rejected Inamed's application in part because the company relied on projections and did not directly study its implants' reliability for longer than three years.
Mentor also did not directly study long-term use, but instead offered laboratory stress testing that the company said was proof that the implants could withstand up to 60 years of wear and tear in the body.
"These are two different devices," said panelist Stephen Li, who supported Mentor's application after opposing Inamed's bid the day before. "They [Mentor] had an extremely low rupture rate."
Still, several panelists said they were uneasy with how the patients and physicians would use the implants because of the extreme difficulty in detecting ruptures in the two companies' studies. More than 85% of ruptures in Inamed's study occurred with no symptoms, while all of the ruptures in Mentor's trial had no outward signs and required imaging of the breast (an MRI scan) to detect them.
That fact led several experts to worry that thousands of women could go for years with broken implants in their bodies while there are still some questions about the health effects of leaked silicone.
Thousands of women have blamed ruptured implants for diseases including autoimmune disorders and cancer, though a 1999 Institute of Medicine study found no hard link between the products and systemic disease. Still, that same year, former implant maker Dow Corning agreed to pay $3.2 billion to settle health claims in a major class-action lawsuit.
The problem of "silent" implant rupture led experts to predicate their approval on a recommendation that women undergo an MRI scan five years after receiving their implants and that the devices be removed if breaks are found.
The panel also recommended that all patients be required to receive education and sign an informed consent form before surgery. The panel also recommended that only physicians who undergo a certification course be allowed to use them in surgery.
"The access needs to be limited. Don't just assume physicians have had this training," said Michael J. Miller, MD, a panel member and plastic surgeon from the University of Texas.
Panelists took the unusual step of requesting that silicone implants be closely tracked to allow the company and regulators to follow each device to individual patients in the event of future problems. The committee also said that the company must continue its study of breakage rates for seven more years.
"I think that it's still too soon to accurately define what is happening to that group," said Patricia Newburg, MD, a panel member and dermatologist from Scarsdale, N.Y. Newburg pointed to data that showed that women with ruptured implants were more likely to experience joint pain consistent with connective tissue disease, though the small study had too few participants to be significant.
"In short, there's too much uncertainty," said Newburg, who voted against both companies' implants.
Levine told the panel that the Mentor's "postmarket commitments would be followed."
Tough Choices for FDA
This week's split vote is likely to put FDA officials in a difficult position when deciding if, and how, to approve silicone implants, said Diana Zuckerman, president of the National Research Center for Women and Families, a group that opposes their approval.
The FDA withheld approval of Inamed's implants despite an advisory panel's recommendation 18 months ago, citing incomplete safety data. As on Wednesday, the panel at that time insisted on a set of strict approval conditions agency officials did not attempt to enforce.
"I think there will be a lot of pressure to take the same action on both" Inamed and Mentor implants, Zuckerman told WebMD. "It shows a level of concern that's not consistent with approval."