An already existing vaccine for breast cancer- at the Mayo Clinic?

Well it’s still in the maybe category but .......we have a vaccine for cervical cancer, so of course it’s possible. Without full trials, it’s presumptive to say it’s ‘safe’ or for that matter, useful/effective for all. There’s ‘many a slip between cup and lip’!! But there’s nothing inherently unthinkable in the concept.  There have been so many developments in the last decade, it’s very exciting.