A radiopharmaceutical consisting of ethylenedicysteine-deoxyglucose (EC-DG) labeled with the metastable radioisotope technetium Tc-99 (99mTc). Upon administration, technetium Tc 99m ethylenedicysteine-deoxyglucose accumulates in cells with increased metabolic activity such as proliferating tumor cells; tumor tissue may then be imaged using gamma scintigraphy. Check for active clinical trials using this agent. (NCI Thesaurus)