It's been my experience that if you ask whether you need chemo or not, your doctor will recommend it regardless.  The things Laurie mentioned are a big factor when it comes to chemo, but the oncotype test is really the one that determines whether chemo would be beneficial to you or not. Chemo is a systematic drug used to kill off rouge cells - radiation is a localized treatment that kills off any cells remaining at the site. The tests you mentioned above are focusing on whether or not you carry what's called the breast cancer gene and if you are at risk of osteoporosis - not if chemo would be beneficial to you or not. Your best bet is to talk with your doctor - see what he advises and why (if he is recommending chemo there might be a very good reason for it) - find out about your pathology, ask for an oncotype test, and go from there. Good luck! Angi