Mentor Corp., which hopes to win Food and Drug Administration approval soon to sell its silicone-gel breast implants for general cosmetic use, faced a problem last year as it prepared to distribute to doctors the demonstration models that prospective customers would try on for size: The implants sometimes left behind an unsettling slick of silicone oil.
A former senior engineer with the company told the FDA last month that he and others were asked to solve that problem and came up with a less permeable material for the one-inch patch that seals a hole left by the manufacturing process. But despite urging from its staff, the company never made the same modification to the devices destined to be implanted in women who want to have their breasts restored after surgery or enlarged, the engineer said in a letter to the agency.
"I am very concerned about the safety of women using these breast implants if they were to become widely available as an FDA-approved product," wrote the engineer, who provided a copy of his letter to The Washington Post on the condition that he not be identified because of family and job concerns. He also wrote that he believed it was misleading to show patients the modified devices but implant the others.
The former Mentor engineer's allegations are now before the agency and several congressional oversight committees, adding a new factor to the long-running debate over wider use of silicone breast implants.
Daniel G. Schultz, director of the FDA's Center for Devices and Radiological Health, confirmed last week that the agency received the letter, adding, "We are evaluating it and do take it seriously."
Possible health complications from silicone-gel "bleeds" are among the issues the FDA is assessing as it moves toward a decision on two applications to allow unrestricted sale of silicone implants for breast enlargement for the first time since 1992. Mentor and Inamed Corp. received letters from the FDA saying that their devices are "approvable" if certain conditions are met, and both companies have undergone final plant inspections by the agency.
Controversy lingers, however, over the safety of the implants. Several officials inside and outside the FDA -- as well as some members of Congress, including Rep. Rosa L. DeLauro (D-Conn.) -- have urged agency officials to investigate the issues raised by the Mentor whistle-blower. Susan Wood, who recently resigned as head of the FDA's Office of Women's Health, said she contacted top officials in August and was assured the agency would investigate.
Schultz said the FDA's device center has spent more time reviewing breast implants than any other product during his 11 years as a manager there. If the devices are approved for wider use, he said, "all the good, bad and indifferent" information on issues such as gel bleeds will be fully disclosed so women can make informed decisions.
Earlier, FDA spokeswoman Julie Zawisza said the agency had received sufficient gel-bleed data from Mentor and was not concerned about the issues being raised. She also said the agency would not object if Mentor used a different demonstration model for sizing as long as the practice was "not misleading."
One member of an FDA advisory panel that reviewed the Mentor and Inamed applications in April said she was disturbed to learn that women were trying out a modified Mentor device without knowing that the actual implant might be different. New York dermatologist Amy Newberger, who opposed both applications, said of the Mentor engineer's allegations: "On the face of it, that causes me real concern."
In a statement, Mentor, which is based in Santa Barbara, Calif., dismissed the issue, saying the FDA letter regarding approvability was based on safety and efficacy data that considered all aspects of the device, including the patch. That data, the statement said, showed that gel leakage was "more than a million fold below toxicological levels of concern."
The Mentor statement did not address the charge that women were choosing size with an implant different than the one they would receive, but it said "new technology development is an ongoing process at Mentor for all of our products."
More than 264,000 breast implant surgeries were performed last year for cosmetic reasons, according to the American Society of Plastic Surgeons. An additional 63,000 were done for women who had mastectomies. Since the 1992 FDA decision to restrict silicone-gel implants because of health concerns, the devices have been available only to mastectomy patients and women willing to participate in a clinical trial. Most women seeking breast enlargement have had to use saline-filled models, which many say produce a less natural result.
The former senior engineer left Mentor this past spring for another company. In his letter to the FDA, he said that after it became known that he was raising concerns about the Mentor implants, the company made accusations against him that resulted in an indictment involving disputed company property.
In the letter, the engineer said he assumed that Mentor "will use those accusations as their defense against the statements I have made in this letter." He said he had been advised not to discuss the accusations, but "fortunately, the statements I have made in this letter can all be checked out by the FDA."
The issue of silicone-gel bleed or diffusion is sensitive because small amounts of silicone oil are known to seep out of all implants. Improvements to the shells, or outer envelopes, have significantly reduced leakage since the devices were taken out of general use, however, and studies have shown that most silicone that leaks out remains in the cavity created by scar tissue around the implant.
Nonetheless, the issue remains scientifically contentious and emotionally raw. Although studies generally show that silicone in the body does not cause ill effects, some women have reported disturbing consequences. Several told the FDA advisory panel that silicone oil had seeped out of their foreheads, eyes and elsewhere.
During the panel's hearings, the FDA reported that Mentor's patch is not made of the same low-bleed material as the rest of the shell. Inamed's competing device has a low-bleed shell and patch.
The former Mentor engineer first took his concerns to a women's health advocate, Diana Zuckerman of the Washington-based National Research Center for Women & Families, who has been critical of the lack of long-term safety studies of breast implants. She helped him contact the FDA to talk about his experiences at Mentor.
"If it is true that the patch is low bleed for 'sizers' and high bleed for the real implants, it suggests that the company cares more about silicone oil leaking onto doctors' desks than in patients' bodies," Zuckerman said. She said new research into low but constant exposure to chemicals such as silicone suggests that most women will tolerate it, but some will have long-term health problems.
In his letter, the engineer wrote that he and former colleagues had created an effective and inexpensive low-bleed patch for the implant samples. He also said that although low-bleed patches cost "a few pennies extra for each implant," the company decided not to modify the implants sold to women. He speculated that the company did not want to jeopardize its application by having to test a modified patch.
Mentor officials declined to comment on the engineer's specific charges. But the company's Web site advises women that there is no reason to worry about the "the myth of bleed."
"Minute amounts of 'bleed' occur in all breast implants," the Web site says. "It is important to note that all Mentor gel implants are low bleed. World-wide studies on the subject of bleed have not linked it to illness in patients."
During the April advisory panel hearing, an FDA staff report described three tests the company had undertaken to measure gel bleed. The reviewer concluded that all were of limited value in determining what might happen in the body. The gel bleed issue -- as well as the issue of Mentor's patch -- was barely discussed by the expert panel, which ultimately recommended that the FDA approve Mentor's product but not Inamed's.
FDA spokeswoman Zawisza said: "Although Mentor's gel bleed testing was incomplete at the time of the April panel meeting, Mentor subsequently addressed the outstanding issues." She did not provide further details.