Silicone molecules from breast implants can initiate processes in human cells that lead to cell death. Researchers from Radboud University have demonstrated this in a new study published on 12 June in Scientific Reports.
“However, there are still many questions about what this could mean for the health effects of silicone breast implants. More research is therefore urgently needed,” says Ger Pruijn, professor of Biomolecular Chemistry at Radboud University.
The possible side effects of silicone breast implants have been debated for decades. There are known cases where the implants have led to severe fatigue, fever, muscle and joint aches, and concentration disturbance. However, there is as yet no scientific study demonstrating the effect silicone molecules can have on human cells that could explain these side effects.
Silicone in the body
It is a known fact that breast implants ‘bleed’, i.e. silicone molecules from the implant pass through the shell and enter the body. Earlier research, in 2016, by Dr. Rita Kappel, plastic surgeon, and Radboud university medical center, found that silicone molecules can then migrate through the body via the bloodstream or lymphatic system.
The biochemists at Radboud University next asked themselves the follow-up question: what effect might silicone molecules have on cells exposed to it?
Experiments with cultured cells showed that silicones appeared to initiate molecular processes that lead to cell death. “We observed similarities with molecular processes related to programmed cell death, a natural process called apoptosis that has an important function in clearing cells in our body.
This effect appeared to depend on the dose of silicone and the size of the silicone molecules. The smaller the molecule, the stronger the effect,” according to Pruijn.
To investigate the effect of silicones on human cells, the researchers have added small silicone molecules—which also occur in silicone breast implants – to three different types of cultured human cells. “One cell was more sensitive to the effect of silicones than the other two cell types. This suggests that the sensitivity of human cells to silicones varies.”
The effects the researchers have found lead to many new questions. “We observed that silicones induce molecular changes in cells, but we don’t know yet whether these changes could, for example, lead to an autoimmune response, which could in part explain the negative side effects of implants,” says Pruijn.
“Caution is advised with drawing conclusions based on these findings because we used cultured cells in our research, not specific human cells such as brain cells or muscle cells. Further research is required to get more clarity.”
Silicones  should not be confused with the chemical element, silicon, which is part of the composition of silicones. Silicones are peculiar. Unlike many other silicon-containing compounds or materials (e.g., SiO2, quartz mineral) silicones do not occur in nature. They are entirely synthetic.
They were first synthesised ca. 1900, and the term “silicones” was invented to describe them. Silicones are polymerised siloxanes (a.k.a. polysiloxanes). They are mixed inorganic-organic polymers with the chemical formula (R2SiO)n where R is an organic side group (e.g., methyl, CH3) attached to a siloxane …-Si-O-Si-O-Si-O-… “backbone” or chain (fig. 2A, B). The specific example shown, polydimethylsiloxane (PDMS), is the most common polysiloxane . Since the chains must be terminated, the complete PDMS formula is CH3[Si(CH3)2O]nSi(CH3)3. PDMS is an oily, sticky liquid with a viscosity that increases as the average chain length (molecular weight) is increased.
PDMS is the basis for the both breast implant silicone gel and the silicone rubber sac or shell which contains the gel. The molecular weight of PDMS (or any polymer) is an average, and thus some PDMS molecules will be far shorter than the average – or even cyclic rather than linear. This is important to the behaviour of PDMS in breast implant gels as discussed later.
Silicones can be liquids, gels, elastomers (rubbers) and even hard plastics. Production of silicones starts with sand (fig. 3) and is accomplished by varying the -Si-O-Si- chain length, using different organic side groups, and chemically cross-linking the polymer chains.
The siloxane backbone, due to its large bond angles and bond lengths (fig. 4) is much more flexible than polymers with a carbon backbone (e.g. polyethylene). As a result all silicones are rubbery to varying extents.
Liquid PDMS also has especially peculiar mechanical properties. It runs and flows if poured slowly, and spreads under the influence of gravity. However, if deformed rapidly, the flexible polymer chains easily become entangled.
As a result viscous forms of PDMS can be molded by hand into a ball – which will bounce if thrown against a hard surface. Silly Putty® is liquid PDMS whose viscosity has been increased by reacting it with boric acid.
The inorganic siloxane backbone also causes silicones and silicone-based materials to have other special properties. Although the -Si-O- linkage is flexible, it is extremely chemically stable, as is the bond between Si and O in quartz mineral (silica, SiO2). Thus silicones can be viewed as liquid or solid polymeric materials which have some properties of ceramics. These include:
– low thermal conductivity;
– high thermal stability – chemical and physical properties change little from −100 to +250 °C;
– high chemical resistance to attack by oxygen, ozone, and ultraviolet light.
For medical use, a consequence of thermal stability and resistance to chemical attack is that many silicone-based materials (e.g., silicone rubber) can be autoclave sterilised without altering their structure or properties.
Silicone breast implant shells are filled with either saline solution (fig. 5) or PDMS silicone gel (fig. 1) – or in some cases with both, in separate compartments. The general consensus is that post-surgical mechanical behaviour of implants filled with silicone gel is more like natural breast tissue .
Gels are defined as substantially cross-linked material systems, usually comprised of polymers (liquid or solid). Cross linking means that many of the starting units of the gel (e.g., polymer chains) are chemically attached to other units at various points, so that they form a 3-dimensional network.
As a result, true gels exhibit no flow as long as their structure is intact . Also, if a true gel is deformed by a non-damaging load, and the load is released, the gel specimen will in time return to its original dimensions.
When a polymer is described as cross-linked, it means a given batch of material has been exposed to a cross-linking method . It does not mean that every molecule is cross linked or that cross-linking is uniform. This is a crucial factor in the behaviour of PDMS breast implant gels. The degree of cross linking is usually controllable, and increased cross-linking results in materials – including gels – which are stronger and stiffer.
Breast implants containing PDMS gels have been produced since the 1960s, and over the years gels with different amounts of cross-linking – and thus different properties – have been used .
PDMS gels with lower amounts of cross-linking may not strictly be gels but instead just rather viscous liquids. Due to the inherent incompleteness of cross-linking, PDMS gels (or viscous liquids) contain 1–2% PDMS molecules of extremely low molecular weight (ca. 3 to 20 siloxane units, molecular weights 20 to 1500) with either linear or cyclic structures .
These small PDMS molecules can pass (“bleed”) quite easily through silicone rubber membranes as described below. Also, their small size means that they can disperse through body tissues with relative ease. Increasing cross-linking of PDMS decreases the amount of these molecules that are free.
In general, the latest generation of PDMS breast implant gels are more highly cross-linked, thus minimising the amount of free low molecular weight molecules available to pass into the surrounding tissues through the silicone rubber shell .
However, even with the latest generation implants, low molecular weight PDMS molecules have been found in the breast tissues of implanted persons – even when the silicone rubber shell is intact .
In addition to low molecular weight PDMS, silicone gels can contain trace amounts of platinum – present because platinum is used as a catalyst to promote PDMS cross linking . Platinum in amounts significantly greater than controls has also been found in the breast tissues of women with silicone rubber shells which are intact .
It is certainly conservative and appropriate to minimise the dispersion of foreign materials into the body from implants of any kind – except drug delivery devices. Also specific concerns have been voiced that low molecular weight PDMS – especially cyclic molecules – might mimic estrogens or CNS-active drugs . In addition platinum can evoke toxic responses . For example, cisplatin (cis-PtCl2(NH3)2), used in tumor chemotherapy, damages numerous types of non-tumorous cells.
Silicon (sic) rubber is a misnomer for silicone rubber, and the misuse appears in the media and even journal publications. The misuse should be avoided as there are industrial silicon rubbers (elastomers filled with silicon particles) . The terms rubber and elastomer are generally interchangeable.
All current breast implants employ a PDMS silicone rubber sac or shell, although in some designs the surface is modified chemically or coated to control leakage or enhance/prevent tissue adhesion.
The exceptional flexibility and extensibility of certain formulations of PDMS silicone rubber (compared to organic rubbers) contribute along with silicone gel to the overall ability of these implants to mechanically mimic breast tissue [5, 13].
Silicone rubbers were first formulated ca. 1940 [1, 12] and were in commercial production and industrial use before 1950. The purpose was to create flexible electrical insulating materials with high resistance to degradation at elevated temperatures or in hostile chemical environments. Thus it was the flexibility of the -Si-O-Si- linkage combined with its ceramic-like properties that made silicone elastomers attractive compared to most organic-based rubber insulators.
PDMS silicone rubbers are thus an old technology. Even their clinical use in breast implants dates back to the 1960s .
Since the technology is an old one, there are few recent journal papers devoted to mechanical and physical properties of PDMS silicone rubbers – except when proposed for some new use: for example in 1997 when PDMS rubbers was considered for use in creating micro-machined chemical sensors . Besides providing a highly stable, flexible insulating material for use in chemical sensors, PDMS silicone rubbers were advantageous because of another property – high gas permeability. This also makes them attractive for contact lens and blood oxyenator applications.
In any case it is not possible to give exact physical or chemical properties for PDMS silicone rubber because there is no such thing as just “plain” PDMS silicone rubber.
Here is why: First, the liquid PDMS starting material can have a range of molecular weights. Then, a selected amount of “nano-particles” of amorphous “fumed” silica (SiO2) filler (fig. 6) is added to liquid PDMS to make higher-performance silicone rubber – e.g., for medical use .
This filler increases strength, tear-resistance and the amount the rubber can be stretched under tension before failure. After adding the particles, a PDMS silicone rubber is then formed by chemically cross-linking the formulation to various extents and in various ways. Thus PDMS silicone rubbers can have a wide range of structures and properties.
Finally, while it is possible to buy finished PDMS silicone rubber stock (e.g., sheets) and make things from it, that is not how breast implant shells are made. The cross-linked, finished PDMS rubber in breast implants is created from liquid components during formation of the shell.
So the only meaningful way to determine composition, structure and properties of breast implant silicone rubber is to use specimens taken from a finished shell. Even then, the results only apply to that particular type of shell. And finally, the structure and properties may well differ from one part of the shell to another part due to differences in forming temperature, pressure, etc.
Silicone breast implant material safety
Colas and Curtis  provided a useful overview in 2004 quoted below. I have modified the quote by inserting reference numbers used in the present article rather than citing author names and year of publication:
“In the early 1990s, these popular devices became the subject of a torrent of contentious allegations regarding their safety. Although the legal controversy regarding silicone gel- filled implants continues in the United States, these medical devices are widely available worldwide and are available with some restriction in the United States.
The controversy in the 1990s initially involved breast cancer, then evolved to auto- immune connective tissue disease, and continued to evolve to the frequency of local or surgical complications such as rupture, infection, or capsular contracture. Epidemiology studies have consistently found no association between breast implants and breast cancer [15–18].
In fact, some studies suggest that women with implants may have decreased risk of breast cancer [19, 20]. Reports of cancer at sites other than the breast are inconsistent or attributed to lifestyle factors . The epidemiologic research on autoimmune or connective tissue disease has also been remarkably uniform and concludes there is no causal association between breast implants and connective-tissue disease [22–27].”
A widely accepted definition of biocompatibility is “the ability of a material to perform with an appropriate host response in a specific situation” . Clearly, no material is universally biocompatible – i.e., elicits an appropriate host response in every form of external or internal body contact, in every tissue, regardless of the quantity of material to which the body is exposed or the length of time of the exposure.
There is a pragmatic solution to determing biocompatibility, and to enabling selection of materials for clinical use. Biomaterials scientists have devised – and some regulatory agencies have adopted – a spectrum of simulated-use in-vitro and in-vivo animal tests. The nature and spectrum of the tests selected for a given use reflect the degree to which use might be dangerous to the host.
The spectrum of tests and levels of acceptable performance increase and reach maximums for potentially life-threatening use (e.g., materials for artificial heart valves). According to the ISO (International Standards Organization) Materials Biocompatibility Matrix, breast implants materials are categorised as Implant Device/Tissue-Bone Contact/Permanent. As a result seven of the eight in vitro and in vivo “Initial Evaluation Tests” are required (all except hemocompatibility), plus two “Supplementary Evaluation Tests (chronic toxicity, carcinogenicity) .
Such simulated-use testing is validated by assessing clinical tissue effects of biomaterials by non-invasive means (e.g., imaging) and invasive means (e.g., tissue biopsy, autopsy). In my opinion, whether or not it is required by law, medical device producers should make sure that both the materials they obtain and their own final products made from them are properly tested for biocompatibility and pass the tests. In vitro and in vivo tests of this type  have been widely used by many producers for many years to evaluate silicone breast implant materials.
The clinical information cited in the previous section indicates that laboratory biocompatibility testing has been effective up to the present. Previous breast implant PDMS silicone gels and silicone rubbers have generally proved to be clinically biocompatible.
Biodurability is the inverse of biocompatibility. A material can be said to be biodurable if the host has a minimal effect on the functional properties of the material in a specific situation. As with biocompatibility, no implant material is likely to be universally biodurable – i.e. retain its functional properties in every form of external or internal body contact, in every tissue regardless of the severity of mechanical loading and the length of time of the exposure.
Like biocompatibility testing, biodurability can be accomplished in the laboratory by in-vitro or in-vivo simulated-use testing. In vitro testing is generally focused on simulated-use mechanical loading in a simulated-use chemical environment, either for a fixed period or until mechanical failure. In any case, the materials are evaluated after exposure for changes in structure and properties.
While in-vitro biodurability testing of PDMS silicone breast implants is certainly done, results are not well-documented in the open literature. Much of this work is done by breast implant material and device producers, and considered a proprietary part of implant development and quality control.
Also, simulated-use is not actual use. It is important that biodurability be evaluated after clinical use. Fortunately, some assessments of long-term biodurability of clinically retrieved breast implant silicone gel and silicone rubber have been done and reported. In a key report  three different kinds of explanted silicone gel-filled PDMS silicone rubber shells with implantation times ranging from 3 months to 32 years were obtained for study. In all, 42 implants and 51 control implants were evaluated along with controls.
Using specimens cut from the shells, mechanical properties (strength, stiffness, elongation to failure, tear-resistance) were determined. The authors also performed chemical extractions to determine shell PDMS molecular weight and low molecular weight extractables. In summary, they stated that:
“The investigation included the major types of gel-filled implants that were manufactured in the United States in a 30-year period… The silicone gel explants investigated in this study included some of the oldest explants of the various major types that have been tested to date.
For assessment of long-term implantation effects, the data obtained in this study were combined with all known data from other institutions on the various major types of gel implants.
The study also addressed the failure mechanisms associated with silicone gel breast implants. The results of the study demonstrated that silicone gel implants have remained intact for 32 years in vivo and that degradation of the shell mechanical and chemical properties is not a primary mechanism for silicone gel breast implant failure.”
Another study  of clinically retrieved silicone breast implant focused on looking for changes in molecular structure of both the shells and the gels using NMR (nuclear magnetic resonance) imaging. The authors stated that:
“Using NMR spectroscopy, as well as NMR relaxometry measurements (T2), no evidence of hydrolysis or other chemical degradation of the cross-linked silicone matrix was observed in specimens from an early breast implant model (Cronin) explanted after 32 years in vivo or a more recent Silastic1 II model after 13 years in vivo.
In addition, no appreciable differences were seen in T2 relaxation times comparing explanted breast implants to suitably-matched non-implanted controls, further underscoring the biostability of the cross-linked silicone shell and gel. Our T2 data and resultant interpretations differ from a 2004 report by the NMR lab at the University of Münster, highlighting the importance of suitable non-implanted controls and sample preparation.”
The implants evaluated for biodurability in these studies were ones in common use, fabricated from silicone starting materials advertised as medical-grade. They constitute ample evidence that at least some widely-used PDMS silicone implant gel and rubber materials demonstrated substantial biodurability.
Clinical rupture rates
What the above studies do not provide is information on a key aspect of clinical biodurability. From a materials performance standpoint, the key information surgeons and prospective patients need is the cumulative likelihood over time that silicone implants will rupture.
Fortunately, the reports cited previously (e.g., in the quote from Colas and Curtis ) suggest that breast implant rupture and disease processes have not shown a high correlation. However, rupture can certainly have cosmetic (appearance) consequences. On the other hand, the literature [2, 5] suggests that cosmetic changes may occur slowly, with modern highly cross-linked gels tending to stay in place even after shell rupture.
Ruptures certainly do occur though, and this is why some favour saline-filled implants (see again fig. 5). With saline filling (1.) rupture is easily identified by sudden, readily apparent deflation, (2.) saline dispersal is biologically harmless, (3.) there is thus no anxiety related to dispersal of silicone gel and (4.) therefore the patient can decide for mostly cosmetic reasons whether to have further surgery to remove and possibly replace the implants.
The literature contains widely varying reports of the clinical rupture rate of PDMS silicone rubber breast implant shells. In a 2000 study  at least 55% of 687 implants were diagnosed as ruptured at ca. 11 years. In a 2003 study  based on over 500 implants in place 3 years or more, the authors estimated that ca. 16% would be ruptured by 10 years. In a 2006 study  based on 199 implants the authors concluded that 8% are ruptured at 11 years. It seems safe to conclude that the historic rupture rate is >10% at 10 years.
In 2007, two much larger, 10-year, multi-centre, yearly follow-up studies started that may provide a more comprehensive look at rupture rates and other consequences of breast implant surgery. They are taking place in the USA in cooperation with the US Food and Drug Administration .
A different commercial implant is being evaluated in each study. Both studies enrolled ca. 40,000 patients who received silicone-filled implants plus much smaller numbers with saline-filled implants as controls. Follow-up is proving to be difficult. In one study, the follow-up rate for the silicone-filled implants after two years post-implantation was ca. 60%. In the other, follow-up at three years was only ca. 21%.
Professional and regulatory views on clinical biocompatibility and biodurability
There is a general professional and regulatory consensus that silicone-filled silicone rubber breast implants have previously had sufficient clinical biocompatibility and biodurability. For example:
In 2009 an international surgeons organisation, IQUAM (International Committee for Quality Assurance, Medical Technologies and Devices in Plastic Surgery) issued eight general recommendations concerning breast implants. The last one was a positive conclusion regarding clinical biocompatibility and biodurability: “IQUAM calls for the approval of silicone gel-filled breast implants for global clinical use and unrestricted availability to all patients.” 
The USA tends to go its own way in many things. However, in 2011 the US FDA also came to a positive conclusion concerning general clinical biocompatibility and biodurability : “… the FDA believes that silicone gel-filled breast implants have a reasonable assurance of safety and effectiveness when used as labeled. Despite frequent local complications and adverse outcomes, the benefits and risks of breast implants are sufficiently well understood for women to make informed decisions about their use.”
PIP silicone breast implants
In contrast to the relatively “settled” situation described above, a serious problem has emerged. Since 2010 there have been increasing concerns expressed by governmental agencies and health care providers about the biocompatibility and biodurability of breast implants produced by the now-defunct French company, Poly Implant Prosthese Company (PIP).
In recent months the story has received increasing media coverage which has in turn raised public concern. As this article was being written in early February 2012, a formal criminal investigation was apparently under way. The news media had reported required appearances in French courts – and even arrests by French police – of former PIP employees.
In addition to potentially compromising the health of individual women, the dimensions of the problem make it potentially extremely serious socio-economically. According to the UK National Health Service  “More than 300,000 PIP implants have been sold globally in 65 countries over the past 12 years. Europe was a major market but more than half of the implants went to South America.” Various news media have described PIP as “once the world’s third-largest global seller of breast implants.”
The questions which needed answering as this was being written were:
– whether PIP implants are producing more unfavourable clinical biologic responses than is typical for such implants – and if so, why?
– whether the silicone rubber shells of PIP implants are rupturing at a rate higher than normal for such implants – and if so why?
– if clinically serious problems exist, should some or all of the 300,000-plus PIP implants be removed and perhaps replaced? If so, who should pay the potential enormous cost?
The problem became official in France in March 2010. The AFSSAPS (Agence Française de Sécurité Sanitaire des Produits de Santé) issued a two-page announcement suspending marketing and use of PIP implants. The agency issued a follow-up statement in April 2011 . The agency had concluded by then that PIP implants had significant heterogeneity in quality and fragility of the shells, and that the silicone gel in use had an irritant behaviour not found with other implants.
They also stated that there was a “highly variable rupture rate up to 10%” and “leakage of gel through the shell […] with a rate up to 11%.” Further, they stated that “In case of rupture or leakage, storage of gel in axillary lymph nodes can cause pain and/or inflammation” and their removal should be considered. The French agency further recommended that women with PIP implants have an ultrasound scan every six months, and that any suspected rupture or leakage should lead to explantation of both the suspected prosthesis and its mate.
The French agency went further in a statement on 1 February 2012  recommending that in accord with the proposal of the minister, and as a preventative, that all women with PIP implants should have them removed on a non-emergency basis, i.e.:
“Ce rapport conforte la recommandation des ministres de proposer à toutes les femmes, à titre préventif et sans caractère d’urgence, l’explantation des prothèses PIP.”
While completing my writing in early February 2012, I could not find via internet search whether any other countries except France had issued a blanket PIP implant removal recommendation. In early January 2012, the UK National Health Service (NHS) issued an interim report of an “Experts Group” they assembled to address the PIP implant problem .
The report stated that the NHS has already decided that PIP devices implanted at the expense of the NHS will be removed if the patient and her doctor decides it is necessary, and they will be replaced at NHS expense if desired. The Experts Group wrote that it endorses the offer and “It expects providers in the private sector to take similar steps.”
The Swiss (Swissmedic) regulatory recommendations  at the time this article was written were that:
“…women with silicone gel breast implants from the firm ‛PIP’ are recommended to consult their doctor (surgeon) for a check every six months. In the case of pain or any changes to the breast area or armpits, women concerned should have a medical examination without delay.
The removal of intact implants may be simpler than removing them as a result of tears or in the case of inflammation. Therefore, during the checks, women can also discuss the possibility of removing or replacing the implants before the filling material leaks, and without signs of inflammation.
The risks and benefits should be considered on a case to case basis. Should filling material leak out of an implant pouch, or if there is any sign of inflammation in the breast area or the armpits, the expert societies recommend the removal of both implants.”
Swissmedic went on to say that Swiss women with PIP implants “can…be included via their doctor (surgeon) in the register for breast implants created by the Swiss Society for Plastic, Reconstructive and Aesthetic surgery (SGPRAC).”
What is causing this regulatory concern and action? There seems to be a general consensus in the documents cited above (issued by French, UK and Swiss agencies) that ruptures of PIP implants have occurred more frequently than the norm. Also, the documents imply that PIP implant silicone gel disperses more readily into tissues than is the case with implants from other producers and may have an increased potential to elicit an inflammatory response.
The fear is that these PIP implant biodurability and biocompatibility problems stem from the use of non medical grade silicone starting materials :
“In March 2010 the French regulator, Agence Française de Sécurité Sanitaire des Produits de Santé (AFSSAPS), discovered that the manufacturer had been using industrial grade silicone instead of the medical grade specified for the CE mark. AFSSAPS revoked the CE mark…”
Investigative reporters were on the trail of this problem. There were allegations in the media during January 2012  that to some extent three industrial silicone starting materials were used by PIP in producing their implants: Baysilone®, Silopren® and Rhodorsil®.
The first, Baysilone®, is the trade name of a family of PDMS liquids produced by Bayer AG (Germany). No specific medical grades are mentioned in the product literature . Silopren® is the trade name of a family liquid silicone rubbers also produced by Bayer AG and used to form solid silicone rubber objects. Some but not all of the Silopren® family are certified as medical grade .
Rhodorsil® is a family of PDMS liquids available from Bluestar Silicones (France). While the product literature  briefly mentions “Medical uses, excipient, active ingredient” in a long list of applications, I could not find any specific mention of a medical grade product.
The French regulatory agency, AFSSAPS, or other parties may eventually determine which, if any, non-medical grade silicones were used by PIP to produce their implants – and if they were used, whether and how this created clinical biocompatibility and biodurability problems. If non-medical grade materials were used, then it seems likely that liability will be resolved in court.
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33 Hölmich LR, Friis S, Fryzek JP, Vejborg IM, Carsten C, Sletting S, et al. Incidence of silicone breast implant rupture. Arch. Surgery. 2003;138:801–6.
34 Heden P, Nava MB, Tetering JPB, Magalon G, Fourie LR, Brenner RJ, et al. Prevalence of rupture in inamed silicone breast implants. Plastic & Reconstructive Surgery 2006;118:303.
35 (no author named) FDA update on the safety of silicone gel-filled breast implants. 2011. Center for Devices & Radiological Health, U.S. Food & Drug Adminstration.
36 Neuhann-Lorenz C, Fedeles J, Eisenman-Klein M, Kinney B, Cunningham BL. Eighth IQUAM Consensus Conference Position Statement: Transatlantic innovations, April 2009. Plastic & Reconstructive Surgery 2011;127:1368–75.
37 (No author named). PIP breast implants – latest from the NHS. 2 February 2012. http://www.nhs.uk/news/.
38 (No author named). Breast implants with silicone based gel filling from Poly Implant Prothèse company: Update of tests results. 14 April 2011. Medical Devices Evaluation Direction, Vigilance Department. Agence Française de sécurité sanitaire des produits de santé. Republique Française.
39 (No author named). Xavier Bertrand et Nora Berra, ministres chargés de la Santé, ont reçu les conclusions du rapport sur les prothèses mammaires Poly Implant Prothèse, réalisé par la DGS et l’AFSSAPS. 1 February 2012. http://travail-sante.gouv.fr.
40 Keough B. Pip breast implants: Interim report of the experts group. 6 January 2012. NHS Medical Directorate, Department of Health, United Kingdom.
41 (No author named). Defective “PIP” silicone-filled breast implants, Rueckruf_PIP_Silikon-Brustimplantate_(Update_dfe)_2011-12-23.doc, Swissmedic – Hallerstr. 7 – Postfach – CH-3000 Bern.
42 (No author named). Fuel additive in banned PIP breast implants – report. BBC News Europe. 2 January 2012. http://www.bbc.co.uk/news/world-europe-16384708.
43 (No author named). Bayer silicones Baysilon® fluids M. No date given. Bayer AG Inorganics Business Group, Silicones Business Unit, Baysilone Marketing Section. 51368 Leverkusen DE.
44 High Tear Strength Silopren® LSR4600 Series. May 2010. Momentive performance materials, Inc. Columbus OH USA.
45 (No author named). Bluestar Silicones, Oil 47. No date given. Bluestar Silicones France SAS. Lyon France.
Breast implants are among the most well-studied implantable medical devices placed in humans. They have been used in both reconstructive and aesthetic breast surgery for more than 60 years.
The safety of the device has been affirmed repeatedly through extensive long-term studies and further research continues to take place in order to ensure patient safety.1 Recent scientific studies have shown an infrequent correlation between textured breast implants and anaplastic large cell lymphoma (ALCL), which has resulted in a specific subset of textured breast implants to be removed from market secondary to a higher incidence of this disease.2
Such action reaffirms the importance of ongoing research in all aspects of plastic surgery as we always place patient safety first and foremost.
As physicians who took a Hippocratic oath to do no harm, we must adhere to these same scientific standards if we are to meaningfully define the wide range of symptoms that have collectively become known on social media as “breast implant illness.”
This condition has been attributed to any and all types of saline and silicone breast implants and their surrounding silicone shells. It has been postulated that the implant shell itself may have toxins or other yet-to-be-defined elements that cause a myriad of symptoms yet to be articulated in a scientific manner.3
A 2006 study published in the Annals of Chemistry evaluated the total platinum concentration in both patient tissue and breast implant samples. The authors concluded that women with silicone breast implants have platinum levels that exceed that of the general population.4
However, a critical analysis highlighted that platinum concentrations in blood and urine samples showed no statistically significant difference and that both the control and implanted groups were shown to have platinum levels comparable to those in platinum industry workers.
Furthermore, the study design was deemed nonreproducible.5,6 Pinpointing a material explanation for breast implant illness symptoms has been impeded by poor data collection and lack of science and dissemination of misinformation on social media, which places patients with breast implants at risk of making improperly informed decisions.
This is not to say that breast implant illness does not exist—both patient advocacy groups and the U.S. Food and Drug Administration recognize various symptoms as being risks related to breast implants7—but rather that there is no current scientific evidence to support such claims.
It is therefore the responsibility of plastic surgeons to advise patients who may present with symptoms associated with breast implant illness to seek full evaluation by our medical and rheumatology colleagues to ensure we are not missing any type of disease process; the American Society of Plastic Surgeons is taking the lead in working with patients and with the Food and Drug Administration to investigate these widely reported symptoms in an effort to supplant speculation with data and science.
PAST IS PROLOGUE
The breast implant illness discussion is reminiscent of a past era when silicone breast implants were ultimately removed from market by the U.S. Food and Drug Administration in 1992.7 That decision was driven by a lack of adequate scientific and safety data at that time.
In the 1990s, surgeons lacked definitive answers regarding the safety of silicone breast implants, which largely contributed to heightened patient concern. If we step back and look at the culture surrounding breast implants today, we may find ourselves viewing a familiar picture, but with several glaring differences.
Unlike 25 years ago, we now have extensive scientific evidence to support the overall safety of breast implants. However, with the advent of social media, much information that is neither scientific nor proven now receives dissemination through the unfiltered social media echo chamber—and much more widely than a single television report. Hence, there has been significant distortion of the facts and scientific data surrounding breast implants and breast implant illness.
To help our patients and the public navigate this information as it is being spread online through large-scale social media platforms, we must continue to rely on science and ethics.
Today, various social media sites and even several board-certified plastic surgeons can be found preying on the fears of concerned breast-implant patients – and placing them at risk by promoting unnecessary and even dangerous procedures, including en bloc total capsulectomy.
Despite absolutely no scientific evidence to support claims that an en bloc capsulectomy is needed to remove all the toxins and/or elements claimed to cause breast implant illness symptoms, some seem to be forgetting to put science and safety ahead of their own personal grievances or misgivings.
The driving force behind breast implant illness patient support groups is supposed to be improving patient safety and advocating for further research in this important field. If the physicians marketing themselves as “en bloc experts” are so genuinely concerned about the welfare of patients, I call upon them to enroll all of their breast implant illness patients in both prospective and retrospective national outcome studies, and to examine all of their patients’ breast capsules for the specific toxins that they espouse are causing the breast implant illness symptoms. It is, after all, our professional duty and moral obligation to present options based on the best evidence available without misleading patients.
SCIENCE AND SAFETY
Breast implantation is a purely elective procedure, and patients are completely within their rights to pursue device explantation as freely as they are to pursue implantation. There is no debate that the treatment of those with breast implant–associated ALCL is total en bloc capsulectomy. However, this procedure is not without potential morbidity, nor is it recognized as the “standard of care” for explantation surgery.
There is no evidence to support en bloc resection as a necessary procedure for those seeking implant explantation only, or for other purposes including symptoms attributed to breast implant illness. Such a procedure requires a skilled, board-certified plastic surgeon with expertise and experience in this area, as removal of the capsule off the chest wall has significant inherent risks, particularly for patients who have capsules that are adherent to their chest wall.
Board-certified plastic surgeons as a group are well-trained, caring, compassionate, and insightful physicians who seek informed answers to difficult questions through carefully designed research. A prospective study8 found that women who underwent explant surgery of silicone breast implants experienced a temporary decrease in musculoskeletal symptoms and bodily pain, as well as an increase in vitality, mental health, and body area satisfaction, but none of these benefits were sustained.
An additional retrospective study9 found that no pairing of symptoms was associated with or predictive of postsurgical outcomes, and that patients with greater than nine preoperative complaints or symptoms were less likely to perceive an improvement in quality of life compared to those with less than five.
As physicians and as plastic surgeons, we must always put patient safety first in all that we do, and we must work with our patients and the scientific community to continue to seek scientifically backed answers to these difficult questions.
Breast implant explantation is a personal choice and, when performed, must be done in a safe and prudent manner by a board-certified plastic surgeon. Likewise, patients who report breast implant illness symptoms must be taken seriously and cared for appropriately. There is no room for fearmongering to influence a patient’s decision.
- Rohrich RJ, Kaplan J, Dayan E. Silicone implant illness: Science versus myth? Plast Reconstr Surg. 2019;144:98–109.
- U.S. Food and Drug Administration. Allergan recalls Natrelle Biocell textured breast implants due to risk of BIA-ALCL cancer. Available at: https://www.fda.gov/medical-devices/medical-device-recalls/allergan-recalls-natrelle-biocell-textured-breast-implants-due-risk-bia-alcl-cancer#:~:targetText=The.
- Chun HJ; Breast implant illness. Available at: https://www.youtube.com/watch?v=Wog_76ITybU&feature=youtu.be. November 8, 2019.
- Lykissa ED, Maharaj SV. Total platinum concentration and platinum oxidation states in body fluids, tissue, and explants from women exposed to silicone and saline breast implants by IC-ICPMS. Anal Chem. 2006;78:2925–2933.
- Lane TH. Comments on total platinum concentration and platinum oxidation states in body fluids, tissue, and explants from women exposed to silicone and saline breast implants by IC-ICPMS. Anal Chem. 2006;78:5607–5608.
- Brook MA. Comments on total platinum concentration and platinum oxidation states in body fluids, tissue, and explants from women exposed to silicone and saline breast implants by IC-ICPMS. Anal Chem. 2006;78:5609–5611.
- Ashar B. Statement from Binita Ashar, M.D., of the FDA’s Center for Devices and Radiological Health on agency’s commitment to studying breast implant safety. Available at: https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm620589.htm?utm_campaign=09142018_Statement_FDA+Statement+on+agency’s+commitment+to+studying+breast+implant+safety&utm_medium=email&utm_source=Eloqua&elqTrackId=179F06C0C4E20BA8893DDF6B820619AF&. September 14, 2018.
- Rohrich RJ, Kenkel JM, Adams WP, Beran S, Conner WC. A prospective analysis of patients undergoing silicone breast implant explantation. Plast Reconstr Surg. 2000;105:2529–2537.
- Rohrich RJ, Rathakrishnan R, Robinson JB Jr, Griffin JR. Factors predictive of quality of life after silicone-implant explantation. Plast Reconstr Surg. 1999;104:1334–1337.
More information: Carla Onnekink et al, Low molecular weight silicones induce cell death in cultured cells, Scientific Reports (2020). DOI: 10.1038/s41598-020-66666-7