I was diagnosed with Breast cancer 8 months ago. ER+ PR+ Her2 - , 0.4 mm grade II invasive ductal. no chemo. No radiation . I take tamaxofin.Last 2 weeks I have unbearable pain in my knees and hips. I think may be it's related to secondary bone cancer. I had bone scan 8 months ago and had lots of X-ray about 20 and 4 Ct-scan chest and mamogram ..I heard about the risk of radiation and i'm worry about it. what can i do to notice if my pain related to arthritis or no? Is it possible without X-ray? Can tumor marker can detect secondary bone cancer? What can i do to avoid the risk of cancer?