Breast implants don't affect cancer risk - study

Breast implants don't affect cancer risk - study


WASHINGTON (Reuters) - Silicone breast implants do not affect the risk of cancer in women who have cosmetic surgery, according to a company-funded study released on Tuesday that said smoking habits, weight and giving birth had a greater impact.

In one of the longest studies of cosmetic breast implants to date, scientists found women with the devices had an increased risk of lung cancer and a decreased rate of breast cancer compared with the general population, but neither result could be linked to the implants.

"We're not implying implants reduce the risk" of breast cancer, said lead researcher Joseph McLaughlin of the Vanderbilt-Ingram Cancer Centre in Tennessee and the International Epidemiology Institute.

Higher lung cancer rates were likely due to increased smoking, according to the results published in the April 19 issue of the Journal of the National Cancer Institute. An earlier study found women who had cosmetic implant surgery were 2.8 times more likely to smoke than the general Swedish population, researchers said.

Dow Corning Corporation, once the world's largest maker of silicone gel breast implants before U.S. health regulators banned them for most women in 1992, funded the study.

In 1999, the company filed for bankruptcy and spent $3.2 billion (1.8 billion pounds) to settle lawsuits from thousands of patients who alleged silicone implants made them sick.

McLaughlin said the devicemaker was not involved in designing the study, collecting data or analysing results from the study, which began in 1994.

"They had no role beyond the funding," he told Reuters.

His team, which included researchers from Karolinska Institute in Sweden, analysed government data from 3,486 Swedish women who first received implants between 1965 and 1993. On average, women were followed for about 18 years.

OTHER FACTORS

They found 180 total cases of cancer, including skin, ovarian, and brain, among other types that occurred at rates similar to the general population of Swedish women.

Twenty cases of lung cancer were found, compared with an expected 9 cases based on population estimates. Fifty-three cases of breast cancer were reported, compared with an expected 72 cases.

"We do know reproductive and demographic factors do influence (breast cancer) risk," McLaughlin said. "If you're thin -- women who get these implants are typically quite thin -- you have kids early, you have a lot of (kids) ... all those things lower your risk."

The results come as the U.S. Food and Drug Administration considers final approval for silicone breast implants made by two other manufacturers, Mentor Corp. and Inamed Corp., which was acquired by Allergan Inc..

FDA officials have said the products can be widely sold in the United States if certain, undisclosed conditions are met first. Silicone implants are available in other countries.

Some women argue that leaking silicone from implants can cause chronic debilitating illnesses. Studies have shown the devices can cause scarring and other minor complications, but most have not linked them to long-term health problems.

McLauglin said his study was part of a series of research Dow began funding in 1994 at his and other institutions. He said his team expects to complete two additional studies on implants and long-term disease within a year.