Safety of Silicone Breast Implants (1999) / Chapter Skim
Currently Skimming:
Appendix C: Review of the Reports of the Independent Review Group and the National Science Panel
Appendix C: Review of the Reports of the Independent Review Group and the National Science Panel
Pages 505-514
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 505... ...
The report of the IRG was available to the IOM Committee on the Safety of Silicone Breast Implants in fuly 1998. The NSP was established to review and critique the scientific literature on the possibility of a causal association between silicone breast implants and connective tissue diseases, related signs and symptoms, and immune system dysfunction.
|
From page 506... ...
The task of the IRG was "to review the evidence relating to the possible health risks associated with silicone gel breast implants, to examine the issues relating to pre-operative patient information, and to report to the Chief Medical Officer on its conclusions. Silicone injections, hydrogel filled implants, or other filling materials such as oil or saline were excluded from the remit given to the IRG." The breadth of this scope of work is similar to that defined by the statement of task for the IOM committee's study (see Chapter 1 of this report)
|
From page 507... ...
Likewise, although the NSP did not discuss the associations of silicone gel breast implants with neurologic disease, multiple sclerosis was among the connective tissue diseases examined in the report, neurologic symptoms were among the symptoms and complaints reviewed because they are sometimes asserted to be associated with silicone-gel implants, and results from a few epidemiologic studies of neurologic diseases in women with implants were reported. Finally, although the panel report pointed out problems with existing information and identified areas in which knowledge was lacking, no research recommendations were made.
|
From page 508... ...
The NSP membership was reviewed for any financial conflicts of interest, involvement with breast implantation or with litigation of implant matters, or previously expressed public views on the issues at hand. The panel was an ad hoc body of the court; its support came from the Federal Judicial Center, its website has a "fjc.gov" address, and its members were questioned before and after the preparation of the NSP report in a process that was videotaped and made available as testimony in breast implant litigation where relevant (Kolata, N.Y.
|
From page 509... ...
Subjects examined included a brief history of gel implants and regulatory actions; a description of gel implants; and a review of local and perioperative effects, including contracture, infection, gel fluid diffusion, and the consequences, frequency, and detection by imaging of implant rupture. In general, the IRG report contains less detail and less extensive citation.
|
From page 510... ...
The IRG report's findings of the lack of evidence or plausibility for the presence of silica in tissues of women with gel breast implants, the lack of credible evidence for specific silicone antibodies or adaptive immune responses to silica, and the failure to discover reliable biomarkers for a particular silicone associated systemic condition are generally consistent with the committee's views. Existing data do not allow the definite exclusion of systemic or local immune responses associated with silicone breast implants, but no valid scientific evidence currently establishes any such association.
|
From page 511... ...
The second chapter of the NSP report, "Clinical Immunology," summarizes the clinical evidence for silicone induced immune alterations in women with silicone gel breast implants. The panel introduced the discussion in this chapter by examining again what it believed to be the weak adjuvant effect, the NK-cell effects, and the effects in animal autoimmune models of some silicones noting that in general, these effects are of uncertain biological significance.
|
From page 512... ...
In the third chapter of the NSP report, "Epidemiological Analysis of Silicone Breast Implants and Connective Tissue Disease," the panel discussed descriptive epidemiology and diagnostic criteria for specific connective tissue diseases; it also carried out and discussed meta-analyses of 20 epidemiological studies of silicone breast implants, including unadjusted and adjusted effect estimates and studies of "all breast implants" and "gel-only" implants. The panel calculated the power of these analyses under various circumstances and the population attributable fractions for five connective tissue diseases.
|
From page 513... ...
The IRG also reached summary conclusions that there was no conclusive evidence for an abnormal immune response to silicone from breast implants; that there was no epidemiological evidence for any link between silicone gel breast implants and any established connective tissue disease; and that there was no good evidence for the existence of atypical connective tissue disease or undefined conditions such as "silicone poisoning." The IRG also concluded that there was no evidence that children of women with silicone gel-filled breast implants are at increased risk of connective tissue disease and that the overall biological response to silicone is consistent with conventional forms of response to foreign materials, rather that an unusual toxic reaction. In the section on toxicology, it might have been preferable to have relied on information that is available to and reviewable by others, rather than citing data that are confidential.
|
From page 514... ...
, so the source of the NSP's estimate would be of interest. The effect of this difference on the numbers of cases of connective tissue disease theoretically attributable to implants would not be significant, however.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.