Women with silicone or saline breast implants may face a small risk for a rare immune-system cancer.
But health officials need more data to know whether the implants caused the cancer, according to the FDA. The agency still considers implants safe overall and said that women with implants should not change their routine monitoring.
Safety concerns have plagued breast implants before. Silicone implants were banned in 1992 after some women complained of leakage, leading them to become chronically ill. Widespread sales resumed in 2006 after FDA approval.
An estimated 5-10 million women around the world have breast implants.
The FDA said its review found about 60 cases since 1997 of anaplastic large cell lymphoma (ALCL), a type of immune-system cancer. The FDA said "women with breast implants may have a very small but increased risk of developing this disease in the scar capsule adjacent to the implant."
ALCL is rare in women without implants. In the U.S., the disease is found in breast tissue in about 3 women out of every 100 million nationwide without implants.