Harvard researchers have found no evidence that breast implant implants are linked to a decreased risk of breast cancer death or increase in breast tumor growth.
The study of 1,000 women who underwent breast implants found no differences in the number of breast cancers, or risk of having one or more in a lifetime, the Harvard researchers reported Tuesday.
The researchers also found no increased risk of cancer among women who received implants after age 45.
The research was published in the Journal of the American Medical Association.
“There is a very high level of evidence that the risk of developing breast cancer is not associated with breast implants,” said Dr. Stephen Zuckerman, one of the study’s lead authors.
Zuckman said the findings should prompt new trials of implants.
“If this were the case, I think we would have seen a reduction in the prevalence of breast tumors,” he said.
Zipperman said the Harvard study could help researchers understand the role of implants in the development of breast disease.
“This is a pretty important issue because it’s the single largest population study of the effect of implant placement,” he added.
Zillow Inc., the parent company of Zuck.com, said the study had no effect on its bottom line.
The company also said it had not received a single payment from a patient for the study.
The Harvard researchers were not affiliated with the University of Washington and had no conflicts of interest.
Zinkerman and his colleagues used data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results Program (SEER) to examine whether a person had a diagnosed breast cancer before, after, or within a year of surgery.
They looked at data from nearly 6,000 breast cancers diagnosed in the United States between 1980 and 2004.
They then looked at breast cancer risk for women who had received breast implants and for women whose breast implants were removed, but who remained breast cancer free.
They found no difference in the risk for cancer in the years following surgery or in the year after removal, the researchers said.
Other researchers said the data showed that women who got breast implants before age 45 had an increased risk for breast cancer.
“It is reasonable to think that a reduction would be expected in the lifetime risk for developing breast cancers because the women with the highest risk were younger,” said study author and medical ethicist Dr. Robert Califf, who directs the University Health Network Breast Cancer Research Institute at Harvard.
“We don’t have any data to show that that was the case,” Califf said.
“But there is evidence that women with breast cancer are at a higher risk.”
The Harvard study found no increase in the incidence of breast tumor, according to the researchers.
However, the results did show an increased incidence of the type of cancer that occurs in the breast that caused a woman to undergo surgery.
The type of breast-cancer is called epithelial ovarian cancer, which occurs in about 1 in 3,000 to 1 in 5,000 pregnancies.
In that type of ovarian cancer the tumor is in the outer layer of the lining of the breast.
It is often more aggressive than the benign ovarian tumor, which does not cause cancer.
Califf noted that this study included only women who were breast-free at the time of surgery and did not have other symptoms of the disease, such as osteoporosis or infertility.
Calff said there was a need for more studies of the effects of breast implants on the development and spread of breast and ovarian cancers, especially in women who have been treated with chemotherapy and radiation for cancer.
A new study also found that women receiving implants before the age of 45 who were not treated with chemo and radiation had an elevated risk of experiencing breast cancer within a decade of surgery, even though they were free of the condition for a year.
In the second study, researchers found no link between the incidence and severity of breast surgery and the number or location of breast lesions.
The first study found that implants and implants alone do not increase the risk in women undergoing breast surgery.
Calif said he believes the new study provides more insight into the role that implants play in the disease of breast implant.
“The most significant finding in this study is that the effect is not a one-off,” Calif told ABC News.
“In the other studies, the effect was almost entirely explained by the patients themselves, so we know there are mechanisms by which implants influence breast cancer,” Calaf said.
He added that the study was not a random, blinded trial.
The second study found a significant difference between the patients who were implanted after the age 35 and those who were never implanted.
The women in the second group had significantly more breast tumors, and they also had a significantly higher number of malignant tumors in their pelvis.
“Those tumors had no apparent effect on their survival,” Calife said.
A second study of people with breast surgery found no