KEY TAKEAWAYS
- The study aimed to investigate the diagnostic performance of CXCR4-targeting [68Ga]Ga-PentixaFor vs [18F]FDG PET/CT for reliable detection in MZL pts.
- Researchers noticed enhanced disease detection with [68Ga]Ga-PentixaFor in newly diagnosed MZL pts.
In patients (pts) diagnosed with marginal zone lymphoma (MZL), the use of [18F]FDG PET/CT has demonstrated inconsistent diagnostic accuracy. Given the overexpression of C-X-C motif chemokine receptor 4 (CXCR4) in MZL. Aleksander Kosmala and his team aimed to evaluate the potential of CXCR4-targeting [68Ga]Ga-PentixaFor as a novel theranostic target compared to [18F]FDG PET/CT for MZL.
They performed an inclusive analysis involving 32 untreated MZL pts, encompassing (nodal, n = 17; extranodal, n = 13; splenic, n = 2) subtypes. The subjects underwent [68Ga]Ga-PentixaFor and [18F]FDG PET/CT scans within a median period of 2 days. An evaluation of the total lymphoma volume was conducted through visual and quantitative assessments, measuring maximum/peak standardized uptake values (SUVmax/peak) and calculating target-to-background ratios (TBR, defined as lesion-based SUVpeak divided by SUVmean from blood pool). Visual comparisons were made for all target lesions (TL), and quantitative analyses focused on concordant TL evident on both scans. Additionally, MZL subtype analyses were also conducted.
Patient-based results, [68Ga]Ga-PentixaFor successfully identified MZL manifestations in all 32 subjects (100%) (vs. [18F]FDG, 25/32 [78.1%]). Among the 256 identified TL, 49.6% (127/256) were exclusively evident on CXCR4-directed imaging, while only 7/256 (2.7%) were identified on [18F]FDG but missed by [68Ga]Ga-PentixaFor. In the remaining 122/256 (47.7%) concordant TL, [68Ga]Ga-PentixaFor consistently provided higher metrics compared to [18F]FDG: SUVmax, 10.3 (range, 2.53-37.2) vs. 5.72 (2.32-37.0); SUVpeak, 6.23 (1.58-25.7) vs. 3.87 (1.54-27.7); P < 0.01, respectively. Additionally, the TBR on [68Ga]Ga-PentixaFor (median 3.85, range 1.05-16.0) was approximately 1.8 times higher than on [18F]FDG (median 2.08, range 0.81-28.8; P < 0.01). Notably, these findings on image contrast were particularly pronounced in nodal MZL (P < 0.01) and approached significance for extranodal MZL (P = 0.06).
The study concluded that in newly diagnosed MZL pts, [68Ga]Ga-PentixaFor consistently identified more disease sites than [18F]FDG, independent of the MZL subtype. The higher quantitative PET parameters, including TBR, observed on [68Ga]Ga-PentixaFor PET/CT suggest an enhanced and improved diagnostic read-out with chemokine receptor-targeted imaging.
The study is sponsored by the Okayama University, Japan Society for the Promotion of Science, and German Research Foundation
Source: https://pubmed.ncbi.nlm.nih.gov/37943339/
Kosmala A, Duell J, Schneid S, et al. (2023). Chemokine receptor-targeted PET/CT provides superior diagnostic performance in newly diagnosed marginal zone lymphoma patients: a head-to-head comparison with [18F]FDG. Eur J Nucl Med Mol Imaging. 2024 Feb;51(3):749-755. doi: 10.1007/s00259-023-06489-6. Epub 2023 Nov 9. PMID: 37943339; PMCID: PMC10796439.
