Safety of Silicone Breast Implants
A breast implant is a medical prosthesis used to augment, reconstruct, or create the physical form of a breast. Applications include correcting the size, form, and feel of a woman’s breasts in post–mastectomy breast reconstruction; for correcting congenital defects and deformities of the chest wall; for aesthetic breast augmentation; and for creating breasts in the male-to-female transsexual patient.
It is important to understand that the outer shell or envelope of all breast implants is made of silicone. The actual filling substance can vary and it usually consists of silicone gel or saline. Silicone gel implants are currently the commonest type of implants used in Europe due to their superior cosmetic results.
Silicone breast implants and detection of breast cancer
Silicone breast implants and connective tissue diseases
Silicone Breast Implants and Breast Feeding
Silicone breast implants and air travel
What is silicone?
Silicone is a whole family of chemical substances derived from silica, a natural element found in abundance in sand and rocks. Silica is the commonest chemical element on earth after oxygen!.
The formation of silicone from silica is made possible through its combination with oxygen, carbon and hydrogen. The silicone molecules formed are subsequently connected to form chains. Depending on the way these elements are connected and the length of the chains produced, silicone can be in a liquid, gel or solid form.
Silicone products and use of silicone in medicine
Silicone is a biologically inert substance that has been in use for over 50 years in various applications, both in everyday life and in medicine. Silicone is used as a lubricant in every disposable needle, syringe and intravenous tubing. Silicones are used in lipstick, suntan lotions, food processing, skin creams, hair spray, and cosmetics. Over 1000 medical products use silicone as a component or in the manufacturing process including artificial heart valves, joints, and pacemakers.
Are silicone implants safe?
Many patients considering breast implants will no doubt have heard of frightening stories about silicone toxicity or autoimmune/connective tissue disease, due to gel "bleed" or migration. As a result, breast augmentation has, in the last 20 years, received much unfavourable publicity mainly through the irresponsible actions of the media whereby, regardless of the facts, claims have been made with respect to silicone safety.
Silicone products have been extensively studied in the laboratory as well as in clinical studies. Scientific data has also been gathered from more than 2 million women worldwide who have received silicone breast implants. The information derived from all these studies are being presented briefly.
Silicone implants and breast cancer
Breast cancer appears in parts of the breast with high density in lobules and ducts and could spread to the whole body. According to current data one in ten women will develop breast cancer during her life! Due to the high incidence it has been questioned whether silicone increases this risk.
Several studies have shown that silicone breast implants do not increase the risk of developing breast cancer. On the contrary, it is believed that women with silicone breast implants have a lower chance of developing breast cancer. It has also been shown that if a woman with breast implants develops breast cancer, her chances of recurrence are exactly the same with those women who do not have breast implants, and that long-term survival is the same on both groups.
- A study performed in 1986 at the University of Southern California in 3000 women who underwent placement of silicone breast implants between 1959-1980, showed that there is no increased risk of developing breast cancer in women with breast implants, compared to the general population1.
- A further report on this study, published in 1992 confirmed the initial results2.
- In 1992, the University of Calgary in Canada studied more that 11000 women who underwent placement of silicone breast implants between 1973-1986. This study showed that there is no increased risk of developing breast cancer in women with silicone breast implants, despite the fact that the very large sample and the very long period of monitoring could have demonstrated wven the slightest difference3.
- Another study published in 1996, coming from 3 US states, Georgia, New Jersey4. and Washington, monitored 2000 women with breast implants. This study confirmed what the previous studies showed: there is no connection between breast cancer and breast implants
- In 1998, the UK Department of Health asked a group of experts (Independent Review Group – IRG) to study all the available data on silicone breast implants and to issue a consensus on their safety. According to the Report of the IRG, women with silicone breast implants have a slightly lower risk of developing breast cancer5,6.
- Blood from women with silicone breast implants can kill cancer cells in vitro7.
Silicone breast implants and detection of breast cancer
Studies on the effect of silicone breast implants on breast imaging showed that there is no difference in the time of detection of breast cancer between women with and without breast implants, nor in the stage of the breast cancer at diagnosis. But, due to the fact breast implants prevent proper imaging of the breast tissue with classic mammography views, your radiologist should be informed, so that special views can be employed (Eklund’s technique). It has also been submitted that these views could detect small lesions otherwise very difficult to be depicted with the classic mammography1,5,6.
Clinical examination for breast cancer is rather facilitated with the presence of breast implants, as there is a firm surface against which a lesion could be palpated7.
Silicone breast implants and connective tissue diseases
Connective tissue diseases is a group of disorders affecting the connective tissue (fat, bones, joints, mucosa, skin etc) and are due to the development of antibodies against our own body. It had been postulated that silicone breast implants might increase the risk of such diseases with the development of antibodies against silicone. As one can deduct from the studies presented here, there is no scientific evidence connecting silicone implants with connective tissue diseases.
- In 1993 the University of Texas published a study involving 603 women who underwent breast reconstruction following mastectomy between 1986-1992. Two hundred and fifty of these patients received silicone breast implants, while for the remaining 353 autologous tissue transfer was used. The results of this study showed that the incidence of connective tissue diseases between the two groups was the same8.
- In 1994 the Mayo Clinic published a study involving 740 women who received silicone breast implants between 1964-1991 and 1498 women without implants. This study showed that there was no connection between silicone breast implants and connective tissue diseases9.
- A study published in 1995 by Harvard Hospital, studying the medical records of the Registered Nurses in the USA for a period of 14 years (Nurses Health Study Cohort). The study included 87000 women with and without silicone breast implants. The results of this study showed that there is no conenectino between silicone breast implants and connective tissue diseases10.
- In 1998, the UK Department of Health asked a commitee of expert scientists (Independent Review Group – IRG), to study all available data on silicone breast implants and issue a consensus regarding their safety. According to the IRG’s report there is no scientific evidence linking silicone breast implants with connective tissue disease (or other disease for that matter)5,6. (The full 36 page report can be obtained from Silicone Gel breast Implants Independent Review Group on 0044207 972 8000 or it can be downloaded from the internet on http://www.silicone-review.gov.uk )
Silicone Breast Implants and Breast Feeding
Silicone breast implants do not affect the ability to breast feed. Some of the techniques used for breast augmentation though, such as the periareolar approach can reduce the volume of the milk produced as they cut some of the milk ducts. The usual inframammary fold approach does not affect the milk ducts6.
Milk from women with silicone breast implants contain 10 times less silicone than cow’s milk and 90 times less silicone than infant milk formulas!11
Other studies have shown that children from women with silicone breast implants do not have a higher risk for developing diseases compared to other children5,6.
Silicone breast implants and air travel
There is no chance of the implant exploding or bursting whilst travelling in an aeroplane6.
Conclusions
A large number of studies on silicone breast implants have shown that:
- Breast implants do not increase the risk to develop breast cancer
- Breast implants do not prevent the detection of breast cancer
- Breast implants do not increase the risk of developing connective tissue diseases
- Breast implants do not affect breast feeding
- Children of women with breast implants do not have an increased risk of developing disease
- There is no chance of the implant exploding or bursting whilst travelling in an aeroplane
References
1. Deapen DM, Brody GS et al. The relationship between breast cancer and augmentation mammaplasty: an epidemiologic study. Plastic and Reconstructive Surgery 1986, 77(3):361-367
2. Deapen DM, Brody GS. Augmentation mammaplasty and breast cancer: a 5-year update of the Los Angeles Study. Plastic and Reconstructive Surgery 1992, 89(4):660-665
3. Berkel H, Birdsell DC et al. Breast augmentation: a risk factor for breast cancer? New England Journal of Medicine 1992, 326(25):1649-1653
4. Brinton LA, Malone KE et al. Breast enlargement and reduction: results from a breast cancer case-control study. Plastic and Reconstructive Surgery 1996, 97(2):269-275
5. Silicone gel breast implants. Report of the Independent Review Group, Department of Health, UK, 1998
6. Department of Health. Breast implants. Information for women considering breast implants. 2002
7.Richards A. Key notes on Plastic Surgery. Blackwell Publishing, 2002.
8. Schusterman MA, Kroll SS et al. Incidence of autoimmune disease in patients after breast reconstruction with silicone gel implants versus autogenous tissue: A preliminary report. Annals of Plastic Surgery 1993, 31(1):1-6
9. Gabriel SE, O'Fallon WM et al. Risk of connective-tissue diseases and other disorders after breast implantation. New England Journal of Medicine 1994, 330(24):1697-1702
10. Sanchez-Guerrero J et al. Silicone breast implants and the risk of connective-tissue diseases and symptoms. New England Journal of Medicine 1995, 332(25):1666-1670
11. Semple JL, Lugowski SJ et al. Breast milk contamination and silicone implants: Preliminary results using silicon as a proxy measurement for silicone. Plastic and Reconstructive Surgery 1998, 102(2):528-533
Pictures (c) ASPS, ASAPS, AAFPRS, ADAM, Allergan
