Hi @samy. I wish I knew why my cancer metastasized, but the truth is the doctors don't know why some cancers come back and others don't. They do know, however, that tumor size and the number of affected lymph nodes are strong predictors of metastatic risk (I had high numbers in each category). Hormone therapy reduces that risk. Unfortunately it can come with side-effects for some women - I was fortunately to be one of those that didn't experience them. The good thing is that there are a few different drugs in the aromatase inhibitor family, so if one doesn't work, another might. Good luck!