An increasedexpression of carbonic anhydrase IX (CAIX) has beennoted in a variety of cancers,3 and thedevelopment of CAIX recognition-based theranostic radiopharmaceuticalshas become an attractive research venue.1 Numerous CAIX-targeted radionuclide therapy agents are currentlyundergoing various phases of clinical trials.4 This interest stems from their unique characteristics, in whichchemically identical entities can be used for diagnosis and cancertreatment by incorporating various radionuclides. Here, CA9 is linked to cancer.