Silicone Breast Implants: An Oncologic Perspective
In 1992, the FDA decided that silicone gel-filled breast implants would be available only through controlled clinical studies, despite the fact that they had been used for mammoplasty in millions of women around the world
Drs. Gerszten and Gerszten nicely summarize the events leading to the FDAs 1992 decision to limit the use of silicone-filled breast implants. They also discuss the complications of capsular contracture and implant rupture, the controversial association of
silicone implants with autoimmune disease, and the matter of possible breast carcinogenesis. Finally, they review the effects of breast implants on imaging and cancer detection, as well as the treatment of patients with implants who are newly diagnosed with breast cancer.
Results of Recent Studies
One of the major points made in this paper is that the FDA should reexamine its decision to limit the use of silicone-filled breast implants in light of the results of multiple recent studies. The authors describe eight studies, all of which failed to demonstrate a significant increase in connective tissue disorders in women who underwent silicone breast implantation for augmentation.
As far as carcinogenesis, they also cite five studies that showed no increase in the rate of breast cancer development in women who underwent breast augmentation with silicone implants. Although not emphasized in the review, it is intriguing that the studies actually showed a (nonsignificant) decrease in the risk of breast carcinogenesis in the woman with augmentation implants. It is possible, although doubtful, that silicone is a protective factor. It is more likely that the cases (with implants) and controls (without implants) were not well-matched, and that the implanted women had fewer risk factors for breast cancer.
An important point made in this paper is that women who are not experiencing problems with their silicone breast implants should not have them removed and replaced. The small risks of any surgical procedure are likely to be greater than the risks of retaining the implants.
Implants vs Other Breast Reconstruction Techniques
Each of the techniques for breast reconstruction has its strengths and weaknesses. Latissimus dorsi muscle and transverse rectus abdominus muscle (TRAM) flaps used in breast reconstruction have the advantage of being composed of autogenous tissues. Therefore, they do not have the potential for producing the real or speculated sequelae of silicone implants, such as contracture, rupture, autoimmune disease, and carcinogenesis.
These muscle and tissue flaps do, however, have their own set of problems and complications. They all cause some diminution in strength and function. They also lead to longer operative times and hospital stays and generally require longer recovery times. Abdominal scarring, abdominal wall weakness, and back pain are not infrequent in patients who have undergone reconstruction with TRAM flaps.
Breast implantation has the advantage of being relatively quick, easily tolerated, economical surgical procedure. Recovery from breast implantation also occurs more rapidly.
Capsular Contracture and Implant Rupture
Capsular contracture and implant rupture are not unique to silicone breast implants and also occur with saline-filled implants. Contractures are expected inflammatory responses to foreign bodies, and implants should be placed with the knowledge that, in a certain percentage of patients, hardening, tightness, mild to severe pain, and deformity or distortion of the breast may occur.
Implant ruptures are also expected sequelae of trauma to any fluid-filled implant, whether saline or silicone. Implant contractures and ruptures may be uncomfortable and cosmetically unappealing, but they have not been shown to be unsafe.
Detection and Treatment of Breast Cancer in Women With Implants
Breast implants definitely make the interpretation of mammograms more difficult. The use of special mammographic views, in addition to the routine two views, however, can improve the amount of visualized breast and image quality. As the authors mention, prospective studies using these newer mammographic techniques will be of great value in determining to what degree breast implants hinder the detection of cancer, if they do so at all.
One of the most interesting topics in this paper is whether the clinician should consider breast-conservation therapy in a patient with breast implants who is newly diagnosed with breast cancer. The authors nicely review the literature on this topic, which consists entirely of small, retrospective studies.
Breast-conservation therapy is definitely an option in this setting of previous silicone augmentation. Although the number of patients is limited, the cosmetic outcome of irradiating a breast with implants in the retromuscular location is more favorable than irradiating a breast with implants in the retroglandular position.
Irradiation of a breast mound reconstructed with an implant is also feasible and is becoming more common as prophylactic chest wall radiation is administered more frequently after mastectomy.
Summary
From this review of the literature, it is clear that the FDAs policies on silicone gel-filled breast implants should be reexamined. The silicone implant has distinct advantages for breast reconstruction after mastectomy in some patients.
