Take whatever you can!

This is a sneaky disease, and anyone who thinks that "node neg" is a clean bill from mets is betting the farm. Micro mets are likely there as your breast is full of lymph nodes and they could be less than a millimeter away from the tumor area. Without a detailed "map" of your physiology, where the tumor was, etc. there is NO guarantee. Hormone suppressors may not be sideeffect free, but it is worth the time and trouble to do anything possible to deter the cancer.