Theranostics in Neuroendocrine Tumors.

Area of Science:

• Oncology
• Nuclear Medicine
• Radiopharmacology

Background:

• Neuroendocrine tumors (NETs) and pheochromocytomas/paragangliomas (PPGLs) are rare neoplasms originating from neuroendocrine cells.
• Gastroenteropancreatic NETs frequently overexpress somatostatin receptors (SSTRs), while PPGLs typically overexpress the norepinephrine transporter.
• Recent advancements have significantly impacted the diagnostic and therapeutic strategies for these rare tumors.

Purpose of the Study:

• To provide a comprehensive review of current SSTR-targeted imaging and therapy for NETs.
• To discuss the role and outcomes of norepinephrine transporter-targeted therapy for PPGLs.
• To explore the evolving landscape of theranostics for both NETs and PPGLs, including recent treatment availability changes.

Main Methods:

• Review of Food and Drug Administration-approved SSTR-agonist positron emission tomography tracers.
• Analysis of predictive imaging biomarkers for SSTR-targeted therapies.
• Discussion of 177Lu-DOTATATE peptide receptor radionuclide therapy, including retreatment and posttherapy imaging.
• Examination of 131I-metaiodobenzylguanidine (mIBG) theranostics for PPGLs and the implications of its commercial unavailability.

Main Results:

• SSTR-targeted imaging and treatment have revolutionized NET management.
• 177Lu-DOTATATE offers a significant therapeutic option for NETs, with evolving practices in retreatment and imaging.
• Norepinephrine transporter-targeted therapy with 131I-mIBG has shown the best outcomes for PPGLs, though its availability is now limited.
• SSTR theranostics are being explored as an alternative for PPGLs.

Conclusions:

• SSTR-targeted theranostics represent a cornerstone in modern NET management.
• While 131I-mIBG was a key therapy for PPGLs, its unavailability necessitates exploring alternative strategies like SSTR theranostics.
• Continued research and development in theranostic approaches are crucial for improving outcomes in patients with NETs and PPGLs.