Tumor dormancy in the bone

Bone is a common site of metastasis in many cancers including breast, prostate and multiple myeloma. The dissemination of tumor cells into bone is thought to be an early event, often occurring before clinical detection of the primary tumor. Despite this, overt metastases do not usually develop until many years later. When tumor cells arrive in the bone microenvironment they home to the bone metastatic niche (comprised of the endosteal, hematopoietic stem cell and peri-vascular niches). Interactions between tumor cells and the niche promote tumor cell dormancy and/or tumor outgrowth dependent upon environmental conditions. This chapter discusses the mechanisms that drive tumor cell dormancy and progression to metastases along with the current methodologies used by scientists to study these processes.