Study of Rupture of Silicone Gel-filled Breast Implants - 2001

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STUDY OF RUPTURE OF SILICONE GEL-FILLED

BREAST IMPLANTS

(Important Repost)

May 19, 2000

STUDY OF RUPTURE OF SILICONE GEL-FILLED BREAST

IMPLANTS (MRI COMPONENT)

An FDA study on rupture of silicone gel-filled breast

implants was presented at the Sixth World Biomaterials

Congress on May 18, 2000.

The study, performed in Birmingham, Alabama, involved

women who had their first breast implant before 1988.

The majority of the 907 women in this study had

silicone gel-filled breast implants. Some women who

had silicone gel-filled breast implants were invited

to undergo a magnetic resonance imaging (MRI)

examination of their breasts to determine whether

their implants had ruptured. MRI allows the

radiologist to see the breast implant while it is

still inside the breast.

FDA conducted this study because of concerns about the

frequency and results of rupture. Rupture is a concern

because:

Rupture of silicone gel-filled implants may allow

silicone to migrate through the tissues. The

relationship of free silicone to development or

progression of disease is unknown. ·

Rupture is a device failure - the implant is no longer

performing as intended.

Protocol

Women in this study were identified because they had

been in a National Cancer Institute study on women

with breast implants. Women who responded to a

questionnaire in the NCI study were eligible for this

study. This cohort included only women who were

patients at two plastic surgery practices. The 907

women in this study were a subset of 1247 women in the

Birmingham, Ala., area who were part of an NCI study

on breast implants. ·

The rupture study had two parts. In the first part,

907 women were interviewed about surgeries in which

implant(s) were surgically removed (interview

component of the study). ·

One third of the 907 women in the first part of the

study reported that they had at least one surgery in

which their implant was removed and replaced. Women

were also asked the main reason they had their

implants removed, and if an implant rupture was

suspected prior to the surgery.

If women reported that their implant surgery was for a

suspected implant rupture, they were asked about

symptoms that they may have had and about whether they

knew of a possible cause of the rupture.

In the second part of the study, 344 women with

silicone gel breast implants received MRI examinations

to detect possible implant rupture. The women,

selected randomly from the first part of the study,

were invited to have MRI exams when they were called

to be in the study until all the MRI appointments

planned for the study had been filled. The study had

funding for up to 400 MRI exams to be accomplished at

a particular MRI facility under contract for a certain

period of time. Of the 445 women invited to have an

MRI, 80% (359) accepted and had the examination. Women

were invited for the MRI exam without regard to

whether they had symptoms of breast implant rupture.

Those who accepted the appointments and came were no

more likely to think their breast implant was ruptured

than women who declined the examination or did not

come to their appointments.

The 344 women who received MRI examinations had a

total of 687 implants. The average age of the women in

the MRI cohort was 51 ± 8 years. Most women in this

cohort had a single lumen gel breast implant (82%) and

the remainder had a double-lumen gel breast implant

(silicone and saline). For the 677 implants for which

this information was available, the average implant

age was 17 ± 3 years.

Three independent radiologists reviewed the results of

all of the women's MRIs and for each implant,

determined whether it was intact, indeterminate

(suspicious for rupture), or ruptured. The agreement

between the radiologists was very high.

Results:

At least two of the three study radiologists agreed

that 378 of the 687 implants were ruptured (55%). This

means that 69% of the 344 women had at least one

ruptured breast implant.

Radiologists observed that silicone gel had leaked

outside the fibrous scar capsule that forms around the

implant in 85 of the 687 implants (12%). Of the 344

women, 73 (21%) had silicone gel outside the capsule

in one or both breasts.

Factors that were associated with rupture: the age of

the implant, the implant manufacturer, and whether the

device was implanted above or beneath the chest

muscles.

Limitations of the Study:

This cohort included only women who were at two

plastic surgery practices. It is unknown whether the

results of the study might have been different if

patients from other parts of the U.S. had been

included.

Only 80% of those invited to have an MRI examination

agreed.

Many types of silicone gel-filled breast implants were

included in this study.

While MR imaging is considered the best method for

imaging breast implants for rupture, it is not

perfect. Conclusion

MRI examination in this cohort of patients

demonstrated that the majority of women had at least

one ruptured implant.

Funding and Authors:

Funding for this study came from: the Office of

Women's Health, FDA; the Office of the Commissioner;

the National Cancer Institute, NIH; the Office of

Research on Women's Health, NIH; and the U.S.

Department of Health and Human Services. · Authors

were S. Lori Brown, PhD, MPH 1 , S. Middleton,

PhD, MD 2 , Wendie A. Berg, MD, PhD 3 ,

Soo, MD 4 , and Gene Pennello, PhD 1 .

1. Office of Surveillance and Biometrics, Center for

Devices and Radiological Health, Food and Drug

Administration, Rockville, MD 20850

2. Department of Radiology, University of California

at San Diego School of Medicine, San Diego, CA 92103

3. Division of Breast Imaging, Department of

Radiology and Greenebaum Cancer Center, University of

land School of Medicine, Baltimore, MD 21201

4. Department of Radiology, Duke South Hospital, Duke

University Medical Center, Durham, NC 27710