A new vaccine is being tested that could help prevent breast cancer from recurring in some women.

The vaccine's for women who have a high risk of recurrence and whose tumor cells have a specific protein.

That protein is found in 70 percent of cancer cases.

"The vaccine is given to stimulate the woman's own immune system to recognize this protein as dangerous, to stimulate the system to fight it and to kill it."

The vaccine is given once a month, for six months.

Side effects include low-grade fever and inflammation and redness at the injection site.