Nuclear Medicine

Baseline FAPI PET metrics strongly predict survival across solid tumors

This systematic review and meta-analysis included 47 studies with 1430 cancer patients undergoing baseline FAPI PET imaging. Higher FAPI SUVmax was associated with worse overall survival (HR 2.36) and progression-free survival (HR 1.88). Increased FAPI-avid metabolic tumor volume predicted poorer overall (HR 3.33) and progression-free survival (HR 2.42). High total lesion FAP expression similarly correlated with inferior overall (HR 3.35) and progression-free survival (HR 2.45). Quantitative baseline FAPI metrics appear useful for risk stratification and could inform treatment intensity and trial enrichment strategies. 1

[68Ga]Pentixafor PET/CT improves evaluation of chronic bone and soft-tissue infection

This single-centre retrospective study compared [68Ga]Pentixafor PET/CT with three-phase bone and 99mTc-HMPAO-labelled leukocyte scintigraphy in suspected chronic infections. Among 25 suspected foci, 21 were confirmed infected and 14 additional sites served as noninfected controls. Scintigraphy achieved 90% sensitivity and 83% specificity, whereas [68Ga]Pentixafor PET/CT reached 100% sensitivity and 89% specificity. Overall accuracy favored PET/CT (95% vs 87%), though the difference was not statistically significant (p = 0.07). [68Ga]Pentixafor PET/CT correctly identified all infections but had two false positives, suggesting a promising single-scan strategy pending larger validation. 2

Framework for clinical image-based dosimetry in 225Ac targeted alpha therapy

This review addresses challenges of patient-specific dosimetry for 225Ac therapy, including low activity, complex decay, and indirect daughter imaging. Standardized SPECT/CT protocols, robust VOI segmentation, AI-driven processing, and voxel-level analysis are recommended for reliable time–activity curves and dose estimates. Cadmium–zinc–telluride cameras can improve quantitative accuracy and allow faster whole-body acquisitions, supporting practical routine dosimetry. Reduced mixed-model approaches are proposed to balance dosimetric precision with clinical workflow efficiency and reproducibility. A 134Ce/134La PET in vivo generator is highlighted to study 225Ac progeny redistribution and refine theranostic treatment planning. 3

PSMA PET and radioligand therapy now anchor prostate cancer theranostics

This review summarizes how PSMA PET has outperformed CT, MRI, and bone scintigraphy for detecting recurrent and metastatic prostate cancer. The proPSMA trial is highlighted for demonstrating superior initial staging accuracy of PSMA PET versus conventional imaging. FDA approvals of 68Ga-PSMA-11 for imaging and 177Lu-PSMA-617 for therapy establish a full theranostic pathway in metastatic castration-resistant disease. Radioligand therapy with 177Lu-PSMA-617 extends survival in heavily pretreated patients with limited options. Next-generation PSMA ligands and AI-based quantification aim to improve patient selection, dosimetry, and response prediction. 4