Table 4.

Theranostic implications of FAP

Tracer	Radioisotope type	Therapeutic/ Diagnostic (imaging method)	Case number	Administered dose range	Findings	Refs
68 Ga-FAPI-04	Positron emitter	Diagnostic (PET)	38	122–312 MBq	Tracer absorption in tumor and image contrast was high	[128]
68 Ga-DOTA-FAPI-04	Positron emitter	Diagnostic (PET)	8	1.8–2.2 MBq	The diagnostic efficacy of the tracer was higher than [(18)F] FDG PET/CT	[129]
68 Ga-FAPI-04	Positron emitter	Diagnostic (PET)	13	1.8–2.2 MBq	The diagnostic efficacy of the tracer was higher than [(18)F] FDG PET/CT, and its absorption in the tumor was high	[130]
68 Ga-FAPI-2 and 68 Ga-FAPI-4	Positron emitter	Diagnostic (PET)	4	122–336 MBq	Regarding tumor-to-background contrast ratios, tracers had similar or even better efficacy than [(18)F] FDG	[131]
68 Ga-FAPI-04	Positron emitter	Diagnostic (PET)	15	111 to 298 MBq	Primary and metastatic tumors were detected by the tracer successfully. Tracer is a promising agent to determine the stage of lower GI system tumors	[132]
177Lu-FAP-2286	β-particle and Gamma emitter	Therapeutic and Diagnostic (SPECT)	1	5.8 ± 2.0 GBq	Tracer absorption and maintenance in the tumor were high and had a low toxicity	[133]
68 Ga-labeled FAPI	Positron emitter	Diagnostic (PET)	14 (including all GI system tumors)	52–325 MBq	Regarding tumor-to-background contrast ratios, tracers had similar or even better efficacy than [(18)F] FDG	[134]
68 Ga-FAPI-04	Positron emitter	Diagnostic (PET)	15	2–3 MBq/kg	The diagnostic efficacy of the tracer was higher than [(18)F] FDG PET/CT regarding the detection of liver metastases of GI system tumors	[135]

DOTA Dodecane tetraacetic acid, MBq Mega-becquerel, PET Positron emission tomography, CT Computed tomography, ⁶⁸ Ga Gallium-68, [18F] FDG [18F]fluorodeoxyglucose, GBq: Giga-becquerel, ¹⁷⁷Lu Lutetium 177, SPECT Single-photon emission computed tomography