Is a breast cancer vaccine possible? Quoting directly from the Lifetime TV website:

"Dr. Yvonne Paterson, a breast cancer survivor, is developing a possible vaccine that may put a stop to the disease that takes so many lives. The vaccine, Lovaxin B, would teach the immune system how to attack cancer cells and is currently in pre-clinical testing. While the vaccine is far from being ready for public distribution, Dr. Paterson is enthusiastic about the test results they have seen so far. "We found that we can stop the tumor from growing out to 100 days, at which time we stopped measuring since this is a long time for experiments of this type," said Dr. Paterson. The tumors stopped growing or went completely away."

Dr. Paterson is the founder of Advaxis, Inc., a biotechnology company, as well as a Professor of Microbiology at the University of Pennsylvania."

I'm not a scientist, so I don't have any idea whether or not this is feasible, but it sure is a nice dream.