Comparative diagnostic efficacy of 18F-FDG and FAPI PET/CT in primary liver cancers: A systematic review and meta-analysis.
This systematic review and meta-analysis compared fibroblast activation protein inhibitor (FAPI) and 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) regarding diagnostic efficacy in primary liver cancers, focusing on sensitivity, specificity, and clinical applicability.
PubMed was searched (up to July 31, 2024) for studies evaluating FAPI and FDG PET/CT for hepatocellular carcinoma and intrahepatic cholangiocarcinoma. A total of 9 studies involving 214 patients and 416 lesions were analyzed. Study quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Diagnostic parameters were synthesized using R Studio's "Mada" package with a random-effects model. Heterogeneity was assessed via I² statistics.
FAPI PET/CT exhibited superior pooled sensitivity (0.918, 95% CI: 0.862-0.953) to FDG PET/CT (0.472, 95% confidence interval [CI]: 0.309-0.642). FAPI demonstrated lower specificity than FDG (0.464, 95% CI: 0.281-0.647, vs. 0.678, 95% CI: 0.505-0.851). Furthermore, it obtained a higher area under the curve (0.846 vs. 0.627), indicating high overall diagnostic accuracy. Moreover, FAPI demonstrated superior performance in detecting small lesions (≤1 cm) and FDG-negative tumors, particularly in cirrhotic livers. Contrarily, FDG showed better specificity for benign lesions. Across studies, heterogeneity was mainly attributed to lesion size, cirrhosis prevalence, and tracer subtypes.
FAPI PET/CT achieved higher sensitivity and diagnostic accuracy than FDG in primary liver cancers, particularly in early-stage and metabolically heterogeneous tumors. FAPI offers transformative potential for clinical use despite its lower specificity in patients with cirrhosis. To optimize integration into diagnostic pathways, standardized protocols and large-scale validation are needed.
PubMed was searched (up to July 31, 2024) for studies evaluating FAPI and FDG PET/CT for hepatocellular carcinoma and intrahepatic cholangiocarcinoma. A total of 9 studies involving 214 patients and 416 lesions were analyzed. Study quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Diagnostic parameters were synthesized using R Studio's "Mada" package with a random-effects model. Heterogeneity was assessed via I² statistics.
FAPI PET/CT exhibited superior pooled sensitivity (0.918, 95% CI: 0.862-0.953) to FDG PET/CT (0.472, 95% confidence interval [CI]: 0.309-0.642). FAPI demonstrated lower specificity than FDG (0.464, 95% CI: 0.281-0.647, vs. 0.678, 95% CI: 0.505-0.851). Furthermore, it obtained a higher area under the curve (0.846 vs. 0.627), indicating high overall diagnostic accuracy. Moreover, FAPI demonstrated superior performance in detecting small lesions (≤1 cm) and FDG-negative tumors, particularly in cirrhotic livers. Contrarily, FDG showed better specificity for benign lesions. Across studies, heterogeneity was mainly attributed to lesion size, cirrhosis prevalence, and tracer subtypes.
FAPI PET/CT achieved higher sensitivity and diagnostic accuracy than FDG in primary liver cancers, particularly in early-stage and metabolically heterogeneous tumors. FAPI offers transformative potential for clinical use despite its lower specificity in patients with cirrhosis. To optimize integration into diagnostic pathways, standardized protocols and large-scale validation are needed.