WASHINGTON, Aug. 16 (UPI) -- After ordering a moratorium 13 years ago, the Food and Drug Administration is now considering allowing manufacturers to resume selling silicone gel-filled breast implants, although some experts doubt the safety concerns that initially restricted the use of silicone implants have been resolved.
The FDA issued an approvable letter July 28 to Mentor Corp. of Santa Barbara, Calif., for an application to sell the gel-filled breast implants. The letter is an intermediate step in the FDA's process of reviewing new products, and provides a list of conditions that must be satisfied before the product can be sold in the United States.
Mentor said in a statement that it followed the FDA's request for a voluntary moratorium on sales of the breast implants in January 1992, but in July 1992, it made the implants available to breast-reconstruction patients who were in a continued-access study. The study included more than 107,000 patients. If the FDA approves Mentor's new Memory Gel implants, they will become an option for women seeking breast augmentation or reconstruction.
FDA spokeswoman Julie Zawisza told United Press International the company submitted long-term data from at least two researchers, some of it compiled outside the United States.
A second company, INAMED Corp., also of Santa Barbara, has submitted an application to FDA to sell silicone gel-filled breast implants, and the agency is expected to send an approvable letter soon.
"Obviously, we believe we have a good application," an INAMED official who requested anonymity told UPI.
Dr. Sidney Wolfe, director of the Public Citizen's Health Research Group in Washington, said in a statement he would seriously consider filing a lawsuit if the FDA grants full approval to silicone implants made by Mentor or INAMED. He said the implants now in the works are not significantly different from those restricted under the 1992 moratorium.
"A lot of them are exactly the same," Wolfe told UPI.
The INAMED official said that in the past 15 years, manufacturing processes have improved the cohesivity of silicone-gel fillings and the tolerance and structure of the shells. He said the implants subject to the moratorium were second-generation devices, while fourth and fifth-generation implants currently are being sold in Europe.
"The (United States) is well behind the rest of the world," the INAMED official said.
The INAMED official said the texture of newer-generation implants has been compared to that of a Gummi Bear candy. He said INAMED representatives removed the implant's shell at an FDA panel to show it held together better than older implants.
"The product holds its shape," the official said. "It doesn't run."
The INAMED official said the appearance of a breast implant is an important consideration to many women.
"Silicone looks and feels more natural than saline," the official said, adding that silicone-gel implants can be shaped to match the natural teardrop shape of breasts and accommodate the existing tissue of a woman's body, while saline implants, which currently dominate the U.S. market, are by their nature limited to the shape of round water balloons.
Dr. Diana Zuckerman, president of the National Research Center for Women & Families, said the natural look of even the best breast implant fades after a few months.
"In the long run, they really don't have much benefit," Zuckerman told UPI.
She argued that independent studies need to be conducted on the long-term health effects of breast implants, adding that many of the existing studies have been sponsored by former breast-implant manufacturer Dow Corning as part of the company's defense against a class action suit that sought more than $3 billion in damages. The studies, she said, "seemed to be designed to prove that the product was safe, rather than (determine) whether the product was safe."
She said her organization is not opposed to breast implants, but is opposed to unsafe medical products.
"As long as the FDA lets them sell a product that's not so good, there's not much incentive for them to develop a product that's safer and better," Zuckerman said.
She noted she has talked with breast-implant engineers, who described the balloon-like implants to her as primitive.
"It's not made like a sophisticated medical device," Zuckerman said. "You would really want a sturdier product ... for how it's being used in the human body."
Brochures for both Mentor and INAMED saline breast implants on the FDA Web site include the following disclaimer: "Breast implants are not considered lifetime devices. You will likely undergo implant removal with or without replacement over the course of your life."
A Mentor statement, footnoting "Safety of Silicone Breast Implants," a report by the Institute of Medicine -- part of the National Academy of Sciences -- said: "Epidemiologic studies suggest an estimated low rupture rate between 0.3 percent and 16 percent for all silicone-gel-filled breast implants. ... In the rare instance that silicone gel is released, it is extremely unlikely for it to leave the implant."
The IOM report, however, published in 1999 and which compiled the results of studies done on breast implants up to that point, said, "The medical literature on rupture of gel implants includes reports of prevalence ranging from 0.3 to 77 percent."
The report noted that the study with the 0.3 percent value had a sample size of only 307 women, excluded one implant that was covered with sticky silicone, and examined the implants with a relatively insensitive ultrasound. It concluded that rupture frequencies and rates varied greatly based on implant type, model and manufacturer.
The IOM report authors found comparatively few ruptures for the thick-shelled implants of the 1960s, but they noted one study cited found 95 percent of second-generation implants -- the kind subject to the 1992 moratorium, made from 1972 until the mid-1980s -- ruptured within 12 years of implantation.
Mentor's Core Study, included in the pre-market application and presented at a FDA panel in April 2005, reported a three-year overall patient satisfaction rate of 97.2 percent and the rate of confirmed or suspected ruptures as 1.4 percent for the Memory Gel implants under review.
Zuckerman said all breast implants eventually break, and the difference between saline and silicone involves what happens afterwards. She said the rupture of a saline implant is usually obvious, and the consequences are usually no worse than a treatable infection.
Most women with ruptured silicone implants do not know it, however, she said. The only way to know is to have a breast MRI -- which can cost up to $2,000 and is not available in many locations -- or wait until side effects appear, such as pain and changes in breast shape. Such effects can take months or years. By that time, the silicone gel could have leaked into the lymph nodes, where it can spread through the lymphatic system in the same way cancer does, eventually reaching the lungs and brain.
A 2001 study by the National Cancer Institute found women with silicone breast implants have two times the risk of brain cancer, three times the risk of lung cancer and four times the risk of suicide as women who received other kinds of plastic surgery.
A 2001 FDA study found women with silicone gel-filled implants that had leaked outside the fibrous scar around the implant were 2.8 times more likely to report having the disease fibromyalgia, characterized by widespread pain and fatigue, than women with intact silicone implants.
The silicone gel in implants contains platinum as a binding agent. S.V.M. Maharaj, a chemist at The American University in Washington, said she found platinum levels in the bodily secretions of physically symptomatic women exposed to breast implants exceed levels found in the general population. She also discovered that the particular form of platinum in breast implants is highly reactive, meaning it could interfere with body processes and chemistry.
She will present new research at the American Chemical Society meeting this month. She presented to the ACS in August 2004 and at an FDA advisory panel.
Maharaj said "a big chemical difference" between saline and silicone-gel implants is there is no platinum in the saline fluid, although both types feature silicone shells. She said a recent study by Dow Corning found that by the time implants are 20 years old, the few that have not yet ruptured begin to rupture.
All of the studies have focused on silicone-gel implants, she said, adding, there are no similar studies of saline implants, but because the shells are very similar the rate of rupture is presume to be similar.
"That is, perhaps, further justification for keeping (silicone gel-filled implants) off the market," Maharaj said.
She said other occupational and environmental health studies have found platinum can causes asthma, dermatitis, neurotoxicity and occasional anaphylactic reactions.
The Mentor statement said: "Silicone breast implants do contain a low concentration of a neutral form of platinum used as a catalyst in the manufacturing process. Although some forms of platinum, like those used in the treatment of cancers, may exhibit toxicity, the neutral form of platinum used in silicone-gel-filled breast implants is the least toxic of all known platinums. Platinum related health problems in women with breast implants (do) not presently exist."
Maharaj's study surveyed only breast-implant users who also had health problems, which differentiated it from all other such studies. Not all women with breast implants experience health problems, which can make it difficult to help those who do experience them if they are enrolled in studies that do not differentiate, she explained. Of the 23 women in her study, some had ruptured implants and some had intact implants.
Even without trying to clean up the mess of a ruptured implant, removal is more difficult than insertion, and more expensive, Zuckerman said.
"We hear from women all the time who have broken breast implants and can't afford to replace them," she said.
Wolfe said that, in the last three years, 170,000 breast implants have been removed.
"That does not sound safe," he said. "There is no medical device that's been on the market that's as defective as this one."
"Any woman who really understood, who was really given accurate information about the risk, would not choose (breast implants) if she was going to live more than a few years," Zuckerman said.
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Eva Sylwester is an intern for UPI Science News. E-mail: [email protected]
