Updated February 2008

Breast Implants and Mammography: What we Know and What we Don't Know

By Elizabeth Santoro, RN, MPH

There has been a lot of attention given to mammography screening in recent years. Some of this information has been confusing to women---at what age should I first have a mammogram, how frequently should I have repeat mammograms, and are mammograms even effective? These are questions that women both with and without breast implants have been trying to understand. Despite this confusion, the National Cancer Institute recommends that women have mammograms every one to two years once they are age forty and over.[1] But, what does this mean for women who have breast implants? Are women with breast implants faced with different risks when undergoing a mammogram? Will women with implants require special considerations during the procedure? The latest study from FDA scientists helps to answer these questions.

What did the Study Show?
A new study by FDA scientist Dr. S. Lori Brown and colleagues describes adverse events that were reported to the FDA related to breast implants and mammography screening.[2] The authors found 66 adverse events that were reported as either occurring during the mammogram or involving breast implants interfering with the mammogram. Forty-one reports of either silicone and saline breast implants- - almost two out of three reports-- pertained to ruptures that were suspected as happening during mammography. The other 25 reports included delayed breast cancer detection, inability to perform the mammogram due to capsular contracture or because of fear that the implant would rupture, and pain/soreness during and after the procedure.

Description of the Study
This study examined data from the Manufacturer and User Facility Device Experience (MAUDE) database. This FDA database collects mandatory or voluntary reports of medical device adverse events from physicians, breast implant manufactures, consumers, and others. The reports were received between June 1992 and October 2002 for events that occurred between June 1972 and June 2002. The mean age of the implant was 14.5 years, and ranged from 2-29 years.

The use of the MAUDE database has limitations. There were multiple sources that contributed to the database, and the FDA does not verify the information that is provided. Therefore, the FDA cannot guarantee that the information is accurate and complete. Another problem is under-reporting of adverse events, since patient and physician reporting is voluntary. It is well-documented that the vast majority of problems arising from medical products are not reported to the FDA. As a result of these shortcomings, these data cannot be used to calculate the number of new adverse events expected for a given number of people in a defined time period.

Key Implications of the Studies on Implants and Mammograms

Potential Implant Rupture
It has been previously reported by the FDA that all implants will eventually break, and that most women who have implants for ten years or longer will have at least one broken implant.[3] The risk of breast implant rupture is known to increase as the implant ages. A recent study by Holmich and colleagues suggested that during the first ten years a woman has implants, most implants do not break, between 11-20 years most will break, and by the time they are more than 20 years almost all have broken.[4]

Women with implants have been told that mammography is safe for them, but the results of this latest FDA study suggest that the risk of rupture can be exacerbated by mammography.

Brown and her colleagues also reviewed the published research on implant rupture during mammography and found an additional 17 cases reported in medical journals. According to the American Society of Plastic Surgery, approximately half of the women who get breast implants are in their 20's or early 30's,[5] which means that the implants are already broken or vulnerable by the time these women are old enough for screening mammograms.

Mammography may therefore increase the risk of a rupture earlier in the typical lifespan of implants, and the squeezing involved in mammography probably increases the risk of leakage in implants that are already ruptured. The potential risk of rupture or leakage needs to be weighed against the benefits of mammography by each individual woman. For women who are concerned about breast cancer, knowledge of mammography problems might discourage women from getting breast implants, or encourage them to have their implants removed and not replaced. Current guidelines encourage women with breast implants to have regular mammograms provided that the technician knows the woman has implants prior to the procedure and that special techniques are utilized.[6] In light of this new research, those guidelines need to be reconsidered, especially for women with silicone gel breast implants, where leakage can cause permanent disfigurement and has unknown health risks.

Delayed Breast Cancer Detection
Breast implants can interfere with the detection of breast cancer, because the implants can obscure the mammography image of a tumor. Implants therefore have the potential to delay the diagnosis of breast cancer. Although mammography can be performed in ways that minimize the interference of the implants, the most recent research by Miglioretti and colleagues indicated that even so 55% of breast tumors were missed, compared to 33% of tumors for women without implants.[7] There is no research evidence that implants cause breast cancer, or that delays in diagnosis caused by implants have significantly increased the risk of death.[8] Miglioretti and colleagues found that among newly diagnosed breast cancer patients who did not have any symptoms, the augmented women had larger tumors than those who did not have implants; overall, however, the women with implants were not diagnosed at a later stage of breast cancer compared to the women without implants.[7] Nevertheless, for an individual woman, a delay in diagnosis could potentially result in death, and more research is needed to determine how often that happens, and under what circumstances. From a public health perspective, delays in diagnosis could potentially necessitate more radical surgery: a cancer that could have been treated at an earlier stage with breast-sparing treatments, such as lumpectomy, may instead require a mastectomy. [9,10]

Avoidance of Mammography
This study also found that implants sometimes make it impossible to perform a mammogram. This can happen for two reasons. First, conditions such as capsular contracture, where the scar tissue around the implant tightens and causes the breast to become hard and misshapen, can make it very difficult or even impossible to perform the mammogram. [11,12] The compression of the breast that is required in order to perform the mammogram can be extremely painful if there is capsular contracture, and in some cases the hardness of the breast makes it impossible to compress the breast for the mammogram. Some women avoid getting mammograms because they are afraid of rupture and the latest research indicates that this is a reasonable concern.

Biomaterials testing of breast implants indicates that implants should only break under the most traumatic circumstances, and yet implants break for no apparent reason, as well as under pressure from mammograms. [13] It is difficult to know how much risk a mammogram increases the risk of rupture since so little is understood about why implants break and under what circumstances.

What Does this Mean for Women?
Women considering breast implants and women with breast implants need to be informed consumers, and that includes knowing about the problems that arise from having mammograms with breast implants. This is true for all women, but especially breast cancer patients who may use implants on a healthy breast so that it will match the reconstructed breast after a mastectomy. (Detection of cancer in the reconstructed breast is unlikely to be a problem because the risk of cancer in that breast is so small). Since breast cancer survivors are at greater risk for breast cancer in the breast that was not removed, compared to women who have not had breast cancer, survivors should have regular mammograms of the surviving breast, and need to know the risks.

Women with breast implants and those considering breast implants need to know that they will have a different mammography experience than women without implants, since standard techniques for compression and imaging are ineffective with implants. The special techniques used will push the implant back to try to move it out of the way, and extra views will be taken. Even so, mammograms performed on women with implants will still miss more tumors than is typical of mammograms for women who do not have implants. [7,14] In addition, women with implants should expect that mammography will require more views and take longer, thus costing more and exposing them to increased levels of radiation. Unfortunately, the most common problem, capsular contracture, can make mammography more painful, less accurate, or even impossible to perform. In such cases other, more expensive tests, such as an MRI or ultrasound, may be required.

Women also need to understand that even if breast implants do not cause contracture or other problems, they will still interfere with mammography and mammograms might still cause rupture and leakage.

The bottom line is that women considering breast implants and those who already have them need to be informed about potential problems with mammography so that they can make the decisions that will help them reduce the risk of breast cancer and avoid the problems that arise with implant breakage and leakage.

References:
1. National Cancer Institute. NCI statement on mammography screening. Accessible at: http://www.cancer.gov/newscenter/mammstatement31jan02

2. Brown L, Ferlo Todd J, Do Lou HM. (2004). Breast implant adverse events during mammography: reports to the Food and Drug Administration. Journal of Women's Health, 13(4): 371-8.

3. FDA. Breast Implant Consumer Handbook 2004. Accessible at: www.fda.gov/cdrh/breastimplants/handbook2004/localcomplications.html#3

4. Holmich L, Friis S, Fryzek J, et al. (2003). Incidence of silicone breast implant rupture. Archives in Surgery, 138: 801-6.

5. American Society of Plastic Surgeons. 2003 Cosmetic Surgery Age Distribution (19-50). Accessible at: www.plasticsurgery.org/public_education/loader.cfm?url=/commonspot/security/getfile.cfm&PageID=12555

6. FDA. Breast Implant Consumer Handbook 2004. Accessible at: www.fda.gov/cdrh/breastimplants/handbook2004/specificissues.html#1.

7. Miglioretti DL, Rutter CM, Geller BM, et al. (2004). Effects of breast augmentation on the accuracy of mammography and cancer characteristics. Journal of the American Medical Association, 291: 442-50.

8. Brinton LA, Lubin JH, Burich MC, et al. (2000). Breast cancer following augmentation mammoplasty. Cancer Causes Control, 11:819.

9. Cahan, AC, Ashikari R, Pressman P, et al. (1995). Breast cancer after breast augmentation with silicone breast implants. Annals of Surgical Oncology, 2:2-12.

10. Karanas YL, Leong DS, Da Lio A, et al. Surgical treatment of breast cancer in previously augmented patients. Plastic and Reconstructive Surgery, 111:1078.

11. Van Rappard JHA, Sonneveld GJ, Twisk RV, Borghouts JMHM. (1998). Pressure resistance of breast implants as a function of implantation time. Annals of Plastic Surgery, 21:266.

12. Phillips JW, deCamara DL, Lockwood MD, Greebner CC. (1996). Strength of silicone breast implants. Plastic and Reconstructive Surgery, 97:1215.

13. Open Panel Discussion. FDA Advisory Panel on Inamed Silicone Gel Breast Implants. October 14, 2003. Gaithersburg, MD. Accessible at: www.fda.gov/ohrms/dockets/ac/03/transcripts/3989T1.htm

14. Fajardo LL, Harvey JA, McAleese KA, et al. (1995). Breast cancer diagnosis in women with subglandular silicone gel-filled augmentation implants. Radiology, 194: 859.