Update on PET Imaging of Neuroendocrine Neoplasms

Positron emission tomography (PET) now complements ultrasound, CT, and MRI by enabling whole-body assessment of tumor biology in neuroendocrine neoplasms (NENs). Somatostatin receptor (SSTR) directed PET is the reference standard for staging, prognostication, and selection for peptide receptor radionuclide therapy (PRRT) in well-differentiated neuroendocrine tumors (NETs), while ¹⁸F-FDG PET identifies aggressive, dedifferentiated components that may be refractory to receptor-targeted strategies. Recent Society of Nuclear Medicine and Molecular Imaging/European Association of Nuclear Medicine (SNMMI/EANM) guidelines standardize SSTR PET/CT procedures and reporting. Emerging advances include fluorinated SSTR ligands (e.g., ¹⁸F-AlF-NOTA-octreotide, ¹⁸F-SiTATE), SSTR antagonists (JR11 family), copper-64 theranostics (⁶⁴Cu-SARTATE), and non-SSTR targets such as GLP-1R, CXCR4, and FAP. Hybrid PET/MRI improves hepatic lesion characterization and reduces radiation in appropriate patients, while CT/MRI remains indispensable for morphology and complications. Integrating multi-tracer PET with anatomic imaging refines risk stratification, PRRT selection, and longitudinal response assessment.