New understanding of breast cancer metastasis to bone
 

In breast cancer patients with metastatic disease, bone is the most common site of metastasis and the most common site of first distant relapse, with roughly half (48%) of breast cancer patients developing bone metastases after treatment.

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Re: New understanding of breast cancer metastasis to bone
 

Another reason many cancers spread to the bones is that the bones are very rich in cells that produce Interleukin 6 and this is important in many areas of cancer cell proliferation and angiogenesis. There is a drug called Sylvant (Siltuxumab) which "soaks up Interleukin 6 but the only approved FDA indication is for Castlemans stndrome