Medical Radioisotopes: Clinical Demand, Production Physics, and Untapped Pathways
Over 40 radioisotopes are currently in use or under development across virtually all fields of modern medicine. Their availability relies on a complex interplay of nuclear physics, radiochemistry, and nuclear medicine. This review provides an isotope-by-isotope map of medically important radioisotopes from the perspective of these disparate yet complementary fields. We address the landscape grouped into three tiers: the established clinical core, including, familiar workhorses such as Tc-99m, F-18, Lu-177; an under-leveraged middle tier including Re-186, Re-188, and Sm-153, and the emerging frontier, radioisotopes with demonstrated but underutilised clinical promise such as Ac-225, At-211, Cu-67, and Sc-47. We discuss the properties of these radioisotopes with respect to clinical applications and their production pathways, as well as the associated nuclear and radiochemical challenges. We synthesise these disparate perspectives to identify situations in which alleviating production-side bottlenecks may improve access and patient outcomes.