Advisers to the Food and Drug Administration cited lingering questions about how long the controversial implants really last before breaking and leaking inside women's bodies as they narrowly rejected Inamed Corp.'s bid Tuesday to bring the products back to the U.S. market.
On Wednesday, rival Mentor Corp. gets its chance to persuade the same advisory panel that today's silicone implants are better than versions sold years ago.
But FDA analyses say Mentor has studied the breakage question for an even shorter period than its competitor did, casting doubt on silicone implants' future.
The FDA isn't bound by its advisers' recommendations, but typically follows them.
Without long-term data on implants' safety and durability, "How we can get an informed consent from our patients?" said New York dermatologist Dr. Amy Newburger as she joined fellow FDA advisers in voting 5-4 that Inamed's implants aren't ready for widespread sale.
"It makes me very uneasy," she said. "I don't feel secure about the safety."
Silicone-gel breast implants began selling in 1962, before the FDA required proof that all medical devices are safe and effective. The implants were banned back in 1992, after thousands of women complained they ruptured and caused immune system diseases, joint problems and even suicides. But medical studies have never been able to prove the link, and now only women who have had breast cancer can opt for silicone, reports CBS News Correspondent Elizabeth Kaledin.
Thirteen years later, silicone implants largely have been exonerated of causing serious or chronic illnesses such as cancer or lupus. But they can cause side effects, including infection and painful, rocklike scar tissue. Also, they can break, requiring additional surgery to remove or replace them — and those ruptures can result in silicone oozing into the breast and, sometimes, farther into the body.
Just last year, the FDA rejected requests by Santa Barbara, Calif.-based Inamed and Mentor to lift the near-ban until those durability questions were better answered.
The companies argue that they've done just that, contending that thicker shells and stickier silicone make newer versions of the implants safer than the originals — and just as durable as salt water-filled implants sold without restriction today.
It's an emotional issue. In an extraordinary daylong hearing Monday, dozens of women pleaded with FDA not to lift the near-ban, telling of silicone globs oozing from their bodies after implants broke, and years of pain even after they were removed.
Don't be swayed by the emotion, Inamed chief scientific officer Dr. Patricia Walker told the advisers on Tuesday. "As horrible and heartbreaking as these testimonials are, we must rely on science," she said.
Inamed tracked 940 patients for three years. In those who had breast enlargement, just 2 percent broke in that period. But 10.6 percent of breast cancer patients suffered breakage in that time period, a difference Inamed attributed to a particular implant model popular for breast reconstruction — a model it says it hopes to redesign.
Those breakage rates suggest that 10 years after implantation, about 14 percent of implants will have ruptured, Inamed concluded.
But FDA scientists sharply criticized that estimate, saying in contrast that as many as three-quarters of implants may break within a decade, because they'll likely become more fragile as they age, a factor Inamed discounted.
Moreover, in Denmark, which more closely tracks implant recipients, one study suggests nine of every 100 implants may break each year, noted FDA scientist Dr. Sahar Dawisha. Calculating with those odds, some 22,500 implants a year might break in this country if silicone-gel models were widely sold, she said.
It's impossible to tell which estimates are right, FDA's advisers concluded Tuesday as they began debating whether Inamed has provided enough proof that its products are reasonably safe enough to sell.
Also troubling, when gel implants break, they seldom cause pain or other immediate symptoms, so the woman doesn't know to seek medical care. Inamed is proposing that women undergo MRI scans every year or two to check if their implants have broken. The advisers agreed that MRI exams are necessary, but they couldn't say how often women should get the exams, which cost hundreds of dollars, or how soon after implantation they should start.
The FDA isn't bound by its advisers' recommendations; indeed, it rejected a 2003 vote from this panel that narrowly supported the implants' return. FDA officials haven't indicated how quickly they will decide this time around.