Jeremie Calais, MD, UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA, outlines the validation of fibroblast activated protein (FAP) PET biodistribution at AACR 2021. A prospective, exploratory study of patients who were scheduled to undergo surgical resection of the primary tumor investigated the incidence and degree of FAP expression by immunohistochemistry and explored whether gallium-68 FAPi-46 PET imaging accurately reflects tumor FAP expression from resected tumor and non-tumor specimens. This interview took place at the virtual American Association for Cancer Research (AACR) Annual Meeting 2021.