Head-to-Head Comparison of 68Ga-PentixaFor PET/CT and FDG PET/CT for Detecting Hematologic and Solid Cancers: A Systematic Review and Meta-Analysis

BACKGROUND. Numerous studies have shown the superiority of PET/CT performed with the use of chemokine-targeted tracer ⁶⁸Ga-boclatixafortide (⁶⁸Ga-PentixaFor, Pentixapharm) compared with FDG PET/CT for oncologic evaluation, although outcomes have varied across tumor types. OBJECTIVE. This study aimed to conduct a head-to-head comparison of ⁶⁸Ga-PentixaFor PET/CT and FDG PET/CT for detecting hematologic malignancies and solid tumors. EVIDENCE ACQUISITION. The PubMed and Embase databases were searched through March 4, 2024, for studies reporting a head-to-head comparison of the detection performance of ⁶⁸Ga-PentixaFor PET/CT versus FDG PET/CT in patients with cancer. Data were extracted from studies on a patient basis for each test in terms of the detection rate, SUV_max, and target-to-background ratio (TBR). The two tests were compared separately for hematologic malignancies and solid tumors. EVIDENCE SYNTHESIS. The meta-analysis included 28 studies (15 studies of hematologic malignancies and 13 of solid cancers), with a total of 493 patients who underwent both tests. For hematologic malignancies, ⁶⁸Ga-PentixaFor PET/CT, compared with FDG PET/CT, showed a significantly higher detection rate overall (relative risk [RR] = 1.19, p < .001) and for bone marrow involvement (RR = 1.69, p < .001), but it showed no significant difference for extramedullary involvement (RR = 1.10, p = .88); ⁶⁸Ga-PentixaFor PET/CT, compared with FDG PET/CT, showed a significantly higher SUV_max overall (mean difference [MD] = 2.26, p < .001) for bone marrow involvement (MD = 4.75, p < .001) and for extramedullary involvement (MD = 5.88, p < .001), as well as a significantly higher TBR (MD = 1.28, p = .03). For solid tumors, ⁶⁸Ga-PentixaFor PET/CT, compared with FDG PET/CT, showed a significantly lower detection rate overall (RR = 0.73, p = .005) but no significant difference for primary lesions (RR = 0.83, p = .11), lymph node metastases (RR = 0.86, p = .04), or distant metastases (RR = 0.64, p = .13); ⁶⁸Ga-PentixaFor PET/CT, compared with FDG PET/CT, showed a significantly lower SUV_max (MD = -8.79, p < .001) and TBR (MD = -3.35, p < .001). CONCLUSION. In a head-to-head comparison of diagnostic performance, ⁶⁸Ga-PentixaFor PET/CT outperformed FDG PET/CT for hematologic malignancies, whereas FDG PET/CT outperformed ⁶⁸Ga-PentixaFor PET/CT for solid tumors. CLINICAL IMPACT. The findings of this study can help guide the selection of optimal imaging strategies in patients with cancer.