RLT is the perfect representation of the theranostics approach where a specific molecule (i.e., PSMA ligand) is first bound with a diagnostic nuclide (i.e., [68Ga]Ga or [18F] for PET) enabling the in-vivo and non-invasive detection of a selected pathology (i.e., PCa). The gene discussed is FOLH1; the disease is posterior cortical atrophy.