Samarium (153Sm) lexidronam

Samarium (Sm) lexidronam (chemical name Samarium-153-ethylene diamine tetramethylene phosphonate, abbreviated Samarium-153 EDTMP, trade name Quadramet) is a chelated complex of a radioisotope of the element samarium with EDTMP. It is used to treat pain when cancer has spread to the bone.