New radiopharmaceuticals and new applications in medicine

All areas of radiology are constantly evolving. At times rapid advances are made because new equipment or pharmaceuticals are introduced. At others the evolution is gradual as established procedures and techniques are refined. The following review of selected areas in nuclear medicine includes both dramatic changes due to new developments and evolutionary changes in established techniques. The first section reviews the development of monoclonal antibodies for use in radioscintigraphy of neoplastic disease. Although many articles have been written about this topic over the years, the clinical applications have suddenly expanded because the Food and Drug Administration (FDA) recently approved one monoclonal antibody for use in the imaging of colorectal and ovarian cancer. It is anticipated that a number of other antibodies will be approved for clinical scintigraphy of both malignant and benign disease and immunotherapy. It is advised that the radiologist performing nuclear medicine procedures become knowledgeable about this expanding area of clinical application. The second section reviews several new radiopharmaceuticals that are being used with increasing frequency for myocardial imaging. The behavior of these tracers is different from that of thallium, and specialized imaging techniques are required. Although the clinical value of these agents is still questioned by some, they are widely used. Familiarity with this topic is recommended. The last section reviews some of the radiopharmaceuticals available for renal imaging and functional evaluation. The relatively new technetium-labeled pharmaceutical that approximates the behavior of hippuran is emphasized. New applications with the renal cortical imaging agent technetium DMSA are also reviewed. A thorough knowledge of the biologic behavior of these tracers and appropriate imaging and measurement techniques is extremely important for their appropriate clinical use.