A radioconjugate composed of the synthetic bombesin (BB) analog demobesin-4 bound to the radioisotope technetium Tc 99m with receptor ligand and gamma-emitting radioisotope activities. Upon intravenous administration, demobesin-4 selectively binds to the gastrin-releasing peptide receptor (GRPR) expressed on the surfaces of various tumor cell types; upon internalization, tumor cells expressing GRPRs bound to technetium Tc 99m can then be visualized using scintigraphy. GRPR, a bombesin receptor subtype, is frequently overexpressed on the surface of tumor cells such as prostate and breast cancer cells. Demobesin-4 was developed for technetium Tc 99m imaging of GRPR-expressing tumor cells. or A substance being studied as a way to find certain types of cancer. It contains a radioactive substance called technetium linked to another substance called demobesin. Demobesin binds to the receptor for bombesin (a substance that is found at higher-than-normal levels on some types of cancer cells). Technetium Tc 99m demobsin-4 collects in cancer cells and a machine is used to find where the cancer cells are in the body. It is a type of radiopharmaceutical and a type of radioimaging agent.