Medical
Bulletin: Breast Implants
The Latest Word from NIH on the Relationship
Between Breast Implants and Cancer and Autoimmunity (originally
published in Scleroderma Voice, 2003 #2)
Editor's note: You can skip directly to the subheads
that interest you, by clicking on these links:
Breast implants were first marketed in the early 1960s, before
the 1976 Medical Device Amendments to the Food, Drug and Cosmetic
Act required medical devices be shown to be safe and effective.
Since 1962, an estimated 1.5 million to 2.5 million U.S.
women have had breast implant surgery.
About 80 percent of breast implants in the United States
are for cosmetic reasons, and 20 percent for breast reconstruction
after breast cancer surgery.
Although implants were originally assumed to be biologically
inactive and therefore safe, many concerns have arisen regarding
possible biologic effects.
Most of the concern regarding long-term risks has focused
on connective tissue disorders, given a number of anectodal
reports of these diseases being diagnosed among women with
breast implants.
As a result, Congress charged NIH with conducting a follow-up
study to examine the health effects of the implants.
A summary of the scientific studies
prior to the NIH study
- Breast Cancer Risk. The most recent studies, which have
been considerably larger than previous studies and have
been able to assess long-term risks, do not support the
notion that implants are related to breast cancer risk.
- Connective Tissue Disorders. Anecdotal reports have suggested
increased risks of certain connective tissue disorders,
including scleroderma, systemic lupus erythematosus, rheumatoid
arthritis, and Sjögren's syndrome.
Attempts have been made in a number of epidemiologic studies
to assess these relationships. However, given that these are
all rare diseases, it has been difficult to draw conclusions
regarding whether there are any alterations in risk among
breast implant patients.
A large meta-analysis after an Institute of Medicine review
of the literature concluded there was not sufficient evidence
to support any relationships between breast implants and these
disorders.
Format of the NIH Study of Breast Implants
This is one of the longest and largest studies to date on
the health effects of breast implants. The participants include
13,500 women who had implant surgery for cosmetic reasons
in both breasts before 1989.
Another unique feature of this study is that the investigators
compared the breast cancer risks of the implant patients to
both the general population and other plastic surgery patients.
Extensive patient data on the potential short-term (rupture)
and longer-term complications (cancer, connective tissue diseases,
symptoms of connective tissue disease) were also obtained.
Results of the NIH Study
Researchers found no significant increase in breast cancer
incidence or mortality among women with implants compared
to controls. In fact, a slight decrease in breast cancer risk
was found during the initial 10-year follow-up period, perhaps
due to medical screening prior to implant surgery.
Patients in the study group experienced lower rates for nearly
every cancer and for total mortality when compared to other
plastic surgery patients, except for an elevation in the risk
of lung and brain cancers, and suicide. While the reasons
for these excesses are unclear, it is possible that the higher
risks observed are due to chance or to factors common to women
who choose to have implants, such as smoking in relation to
the lung cancer excess.
The lower overall mortality rates of the implant population
support previous findings that people who undergo elective
surgery are generally healthier than their peers.
Analyses are currently underway
to assess relationships with connective tissue disorders.
NCI researchers plan to continue to follow the cohort to update
the mortality data over time.
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