Bone Response in Metastatic Breast Cancer Involving Bones

Primary Objectives: * To estimate and compare the sensitivity and specificity of computed tomography (CT), plain radiography (XR), and skeletal scintigraphy (SS) with each other for the assessment of response of bone metastasis in patients with breast cancer. * To estimate and compare the sensitivity and specificity of M. D. Anderson (MDACC) bone metastasis criteria with that of current criteria (UICC, WHO) in breast cancer patients for the assessment of the behavior of osseous metastasis in breast cancer patients. Secondary Objective: * To evaluate the progression free survival (PFS) and overall survival (OS) of each response group (CR, PR, SD, PD) assessed by imaging and response criteria.