By and large, magnetic resonance (MR) contrast media have neither been disease specific nor organ-specific. Injected intravenously, most are rapidly excreted by the kidneys by glomerular filtration. Although several liver-specific contrast media have been created, other organs have not been successfully targeted, and no tumor avid MR contrast agents are available to date.
Because detection of unknown primary tumor and metastatic disease is the “holy grail” of diagnostic oncology imaging, a tumor-avid MR contrast medium would have huge implications for prognosis, therapy selection, and patient outcomes.
Researchers at Roswell Park Cancer Institute (RPCI) have developed a method of using compounds of this invention for diagnostic imaging of hyperproliferative tissues such as tumors and new blood vessel growth as is associated with the wet form of age related macular degeneration.
Invention includes compositions that are chemical combinations of porphyrins and chlorins as well as related tetra-pyrrolic compounds with radioactive elements such as Technetium.sup.99, Gadolinium, Indium.sup.111, and radioactive iodine. When the element can form cations, the compound is usually a chelate with the porphyrin or chlorin structure. When the element forms anions, the compound is usually a direct chemical combination of the radioactive element into the porphyrin or chlorin structure.