Indeed, PET and SPECT probes have already been generated by conjugating the EDB-FN-specific ZD2 peptide to radiotracers like 64Cu-DOTA, 68Ga-NOTA, and 99mTc-HYNIC chelates for improved detection of prostate, pancreatic, and breast cancers 48, 71, 72, respectively. Here, FN1 is linked to breast carcinoma.