Role of molecular imaging in prognosis, diagnosis, and treatment of gastrointestinal cancers: An update on new therapeutic methods

Table 1 Summary of the molecular imaging in gastrointestinal cancers

	Imaging modalities		Diagnosis	Staging	Prognosis/survival	Metastasis	Recurrence	RtT
Liver	PET	18F-FDG-PET-CT			Independent prognostic factor
		11C-acetate vs 18F-FDG-PET	Dual-tracer PET had better sensitivity and specificity vs FDG PET alone	Dual-tracer PET-CT was superior in staging vs contrast CT		18 F-FDG PET-CT has higher	Dual-tracer can predict recurrence after TACE
		Choline vs 18F-FDG PET-CT
		11C-choline vs. 18F-FDG PET-CT	Dual-tracer had higher sensitivity compared w/each one alone		Dual-tracer had better prognostic value compared w/each one alone			Dual- tracer was a better tool for selecting patients for resection or LT
		68Ga-FAPI PET-CT vs 18F-FDG PET-CT	68Ga-FAPI PET-CT is more sensitive vs 18F-FDG PET-CT
		18F-FAPI PET-CT vs. 18F-FDG PETCT	18F-FAPI PET-CT was superior	18F-FAPI PET-CT was superior		18F-FAPI PET/CT was superior in lymph node metastasis vs. distant metastasis	18F-FAPI PET-CT was superior for local recurrence
		68Ga-LNC1007 vs 68Ga-FAPI and 18F-FDG PET-CT	68Ga-LNC1007 PET-CT was superior			68Ga-LNC1007 was superior in skeletal metastases, and peritoneal metastases
	MRI	DWI		Use in staging				Determining response after CT-guided HDR- B
		DWI vs DCE MRI						Can evaluate responses to radiotherapy
Colorectal	PET	18F-FDG PET/CT			Could predict the prognosis
						Dual-time-point 18F-FDG PET/CT could liver metastasis
		68Ga-FAPI PET/CT vs 18F-FDG PET/CT	68Ga-FAPI PET/CT was superior			68Ga-FAPI PET/CT was superior
		Ga-DOTA-FAPI-04 PET/CT vs FDG PET/CT	Ga-DOTA-FAPI-04 PET/CT was superior			Ga-DOTA-FAPI-04 PET/CT was superior
	MRI	Whole body DWI/MRI vs CT				WB-DWI/MRI significantly outperformed CT
		Whole body DWI/MRI	Could improve diagnostic accuracy
		FDG-PET/CT vs MRI vs CT				MRI had highest sensitivity in detecting liver metastasis
	SPECT	99mTc-MAA SPECT/CT				Could detect liver metastasis
Pancreas	PET	FDG-PET						Could predict RtT
		FDG-PET (CT) vs CA-19-9			FDG-PET was univariate preoperative predictor of OS			FDG-PET was superior in predicting pathologic treatment response
			FDG-PET/CT was superior in diagnosis
		FDG-PET/CT			Independent prognostic factor of PFS and OS
					Could predict prognosis
					Independent prognostic values for OS
		FDG-PET/CT and ceCT	Equal potential in Diagnosing			FDG-PET/CT was superior in metastasis detection
				ceCT was superior at nodal staging		FDG-PET/CT was superior
					F-FDG PET/CT was superior	F-FDG PET/CT was superior in predicting LN metastasis
							FDG-PET/CT was superior
		FDG-PET/CT and FDG-PET/MR	Equal diagnostic performance
				18F-FDG PET/MR was superior in TNM staging			18F-FDG PET/MR was superior in liver metastasis
		FDG-PET/CT vs EUS					EUS was superior in detection of locoregional and isolated locoregional recurrences
		68Ga-FAPI PET/CT vs ceCT		68Ga-FAPI PET/CT was superior
		FAPI PET/(CT) vs18F-FDG PET/CT	Equivalent detection ability	Al18F-NOTA-FAPI-04 PET/CT was superior in TNM staging
			68Ga-FAPI PET was superior in diagnosis
			Ga-FAPI PET/CT superior	Ga-FAPI PET/CT was superior		Ga-FAPI PET/CT superior
		FDG-PET/CT vs CA19-9				Both potent predictors for determining the lymph node status
Esophagus	SPECT	C-Met targeted fluorescence molecular endoscopy	It did not improve endoscopy
		99mTc-3PRGD2 SPEC vs [18F] FDG PET/CT	SPECT was superior	SPECT was superior		FDG-PET/CT was superior
		99mTc-3PRGD2 SPEC vs CT				SPECT was superior
	PET	18F-FDG PET/CT			Showed prognostic ability
						Could identify interval metastasis
					Could predict prognosis		Could predict recurrence
							Could predict recurrence
					Could predict prognosis
		68Ga-FAPI-04 PET/CT				Could predict lymph node metastasis
		[68Ga] Pentixafor-PET/CT vs (FDG)-PET/CT	[68Ga] Pentixafor-PET/CT can be complementary to (FDG)-PET/CT				[68Ga] Pentixafor-PET/CT can be complementary to (FDG)-PET/CT
	MRI	CT vs MRI vs EUS		MRI had better diagnostic performance for tumor staging
		DW-MRI						Could predict pathologic complete response
		DCE-MRI						Could predict response to treatment
		FDG-PET/CT vs DWI-MRI			DWI-MRI was independent prognostic factor	DWI-MRI was superior in predicting lymph node metastasis
Stomach	PET	FAPI PET/CT vs FDG PET/CT				FAPI PET/CT is more effective than FDG PET/CT

TNM: Tumor-node-metastasis; PFS: Progression-free survival; FDG: Fluorodeoxyglucose; PET: Positron emission tomography; CT: Computed tomography; DWI-MRI: Diffusion-weighted imaging magnetic resonance imaging; DCE: Dynamic contrast-enhanced; EUS: Endoscopic ultrasound; HCC: Hepatocellular carcinoma; SPECT: Single photon emission computed tomography; TACE: Transarterial chemoembolization; CCRT: Concurrent chemoradiotherapy; OS: Overall survival.