FAP and posterior cortical atrophy: Using quantitative image analysis and a flank xenograft model which consisted of a PCa cell line engineered to overexpress FAP, the authors were able to demonstrate that the amount of radioactivity in the FAP+ tumors of animals receiving the radiopharmaceutical was threefold higher than in the tumors of animals receiving the isotype control radiopharmaceutical, [89Zr]Zr-ICC-IgG, at 72 h p.i. Additionally, the study team was able to demonstrate that FAP targeting could be achieved in an intratibial bone metastasis model.