GRP and breast cancer: More recent advances have seen the emergence of several 99mTc/188Re based theranostics (some limited to preclinical evaluation), including 99mTc and 186/188Re HYNIC-bombesin to target integrin αvβ3 and gastrin releasing peptide receptor (GRPR) (83), 99mTc and 188Re microspheres for selective intraarterial radionuclide therapy associated with hepatocellular carcinoma (84), 99mTc and 188Re DMSA(V) for medullary carcinoma of the thyroid and breast cancer metastases in the liver, brain, and bone (85,86), and 99mTc and 188Re anti-CD66 monoclonal antibody in leukemia and lymphoma (87).