Given the fact that tumor is composed of tumor cells and tumor matrix, as well as that FAP is highly expressed in the most abundant CAF [31,32], hence, a large number of FAP inhibitors that bind specifically to FAP have been developed [9], among which FAPI-04 has been extensively studied for its good tumor targeting effect and already utilized in diagnosing tens of cancers [25]. This evidence concerns the gene FAP and neoplasm.