(RxWiki News) Women who have breast implants don’t have to worry that the implants themselves increase breast cancer risks. A new study suggests implants may affect other cancer risks, though.
Breast implants may be associated with a more advanced breast cancer diagnosis.
And women with implants may be more likely to die from the disease.
These are the conclusions of a review of previous studies.
The authors of the review stressed that the findings should be interpreted with caution because all the studies did not look at important factors.
"Tell your mammography technician if you have breast implants."
Canadian researchers analyzed two sets of studies. One analysis was conducted to determine if breast implants affected the stage at which breast cancer was diagnosed. The second set of studies examined breast cancer deaths in women with implants.
The first set of studies included 12 observational studies that had been conducted mainly in the United States, northern Europe and Canada.
The researchers found that women with breast implants had a 26 percent increased risk of being diagnosed with later stage tumors than were women who did not have implants.
There could be a number of reasons for this finding, including the fact that silicone and saline implants create shadows on the mammogram, according to the authors.
"The implant becomes a wall to the x-rays and anything in front or in back of the implant on the mammograms will be hidden to the radiologist," Daniel B. Kopans, MD, professor of radiology at Harvard Medical School and senior radiologist in the Breast Imaging Division at Massachusetts General Hospital," told dailyRx News.
The implants also make it more difficult to visualize all of a woman’s breast tissue adequately. The implants interfere with compression, and placement can obstruct mammography views.
Mammography technologists currently use what’s called “displacement techniques” to help get around these issues. However, studies have found that these techniques to move the implant out of the view still do not allow for adequate visualization.
Dr. Kopans said, "X-ray technologists have learned to push the implant back toward the chest wall and pull the breast forward to try to reduce this problem. It would be interesting to note if this was done for women in this study. These 'implant displacement' views are better, but cancers can still be hidden. These views are more successful if the implant is behind the pectoralis major muscle (the main muscle on the chest) than if the implant is placed in front of the muscle behind the breast," Dr. Kopans explained.
The researchers then looked at five additional studies to analyze survival data among breast cancer patients with implants.
Women with implants had a 38 percent higher risk of dying from breast cancer than women who did not have implants.
"Our results should be interpreted with caution, considering the current gaps and limitations in the available literature,” the authors wrote.
“The accumulating evidence suggests that women with cosmetic breast implants who develop breast cancer have an increased risk of being diagnosed as having non-localized breast tumors more frequently than do women with breast cancer who do not have implants,” they wrote.
The authors added, “Further investigations are warranted into the long term effects of cosmetic breast implants on the detection and prognosis of breast cancer, adjusting for potential confounders.”
This study was published April 30 in BMJ.
This work was supported through scholarship grants by the Unité de Recherche en Santé des Populations, Cancer Care Ontario, and the Public Health Agency of Canada. No competing interests were disclosed by any of the authors.