FDA Approves Two Silicone Gel-Filled Breast Implants

ROCKVILLE, Maryland—The FDA has approved the marketing of two silicone gel-filled breast implants, Inamed (Allergan) and MemoryGel (Mentor), for use in breast reconstruction in women of all ages and for breast augmentation in women ages 22 and older. The decision supporting the safety and efficacy of the devices came 14 years after FDA placed a moratorium on the use of silicone gel implants except in clinical trials because of concerns they might cause pain, deformity, connective tissue disease, and cancer if they ruptured. Saltwater-filled breast implants remained available.

"FDA has reviewed an extensive amount of data from clinical trials of women studied for up to 4 years, as well as a wealth of other information to determine the benefit and risks of these products," said Daniel Schultz, MD, director of FDA's Center for Devices and Radiological Health. "The extensive body of scientific evidence provides reasonable assurance of the benefits and risks of these devices." Moreover, he said, "we now have a good understanding of what complications can occur and at what rates."

Nonetheless, as part of granting approval to the implants, FDA required the companies to make several postmarketing commitments. Each, for example, must support a separate study that enrolls about 40,000 women and follows them for 10 years after they receive their breast implants. Both companies must also continue their core studies, from which they submitted data to support the implants' safety and efficacy, until all patients have completed a 10-year evaluation.

Although several independent studies and a report by the Institute of Medicine have found no conclusive evidence linking breast implants to connective tissue disease or cancer, the two diseases will be a major focus of the postmarketing trials.

Postapproval Studies

"The postapproval studies will continue to gather information about the safety and effectiveness of the implants," FDA said in announcing the approvals. "Information will be collected about the rates of local complications, rates of connective tissue disease and its signs and symptoms, rates of neurological disease and its signs and symptoms, potential effects on offspring of women with breast implants, potential effects on reproduction and lactation, rates of cancer, rates of suicide, potential interference of breast implants with mammography, and MRI compliance and rupture rates."

Each company must also conduct a focus group to assess laymen's understanding of its product. They are also required to continue laboratory studies to further characterize the types of device failures and to track each implant so that health professionals can be notified of updated product information.

No Lifetime Guarantee

FDA cautioned that women considering a silicone-gel implant should know that breast implants do not last a lifetime, and they will likely need at least one additional surgery in their lifetime.

Other important information physicians should impart to patients include:

• Many breast changes following an implant are irreversible.

• Rupture of a silicone gel-filled implant usually occurs without the woman or surgeon knowing it.

• A woman with silicone implants will need regular MRI screening throughout her lifetime to determine whether her implant has ruptured, starting 3 years after her first implant surgery and every 2 years thereafter.

10-Year Studies

To support the approval of their breast implant applications, the two companies reported early data from their ongoing 10-year core studies. Allergan's 4-year data on Inamed covered 715 women. Mentor provided 3-year data from 1,007 women. Common complications in both studies included hardening of the area around the implant, breast pain, changes in nipple sensation, implant rupture, and the need for additional surgery.

Allergan reported 4-year rupture rates diagnosed by MRI for women who had primary augmentation (2.7%), revision augmentation (4.0%), primary reconstruction (0.0%), and revision reconstruction (0.0%).

Mentor reported MRI diagnosed ruptures at 2 years for primary augmentation (0.5%), revision augmentation (7.7%), primary reconstruction (0.9%), and revision reconstruction (0.0%).

Allergan reported that reoperation was the most common complication among women in its core study. During the first 4 years, 23.5% of the 455 women who had an implant for primary augmentation required a reoperation, as did 35.3% of the 147 patients who underwent revision augmentation surgery.

Capsular contracture was the next leading complication in both patients groups. Other leading problems among the two groups, although not in the same order, include implant malposition, ptosis, need for biopsy, hematoma/seroma, and scarring/hypertrophic scarring.

Among the 98 women in the Inamed study who received implants for primary reconstruction, 40.9% needed a reoperation; the next four leading complications were implant removal with replacement (18.3%), asymmetry (16.4%), capsular contracture grade III or IV (14.1%), and implant removal without replacement (7.8%). Of the 15 women who had revision-reconstruction, 33.3% had reoperation because of nipple complications, scarring/hypertrophic scarring, or capsular contracture; 23 patients with primary reconstruction had 28 implants removed, of which 21 were replaced. The leading reasons for removal were implant malposition, capsular contracture, asymmetry, and patient request for style or size change.

"The silicone breast implant is one of the most extensively studied medical devices," Dr. Schultz said. "This is valuable information for women who may be considering these products."