Imaging of Small-Bowel Neuroendocrine Neoplasms: AJR Expert Panel Narrative Review.

Neuroendocrine neoplasms (NEN) of the small bowel are typically slow growing lesions that remain asymptomatic until reaching an advanced stage. Imaging modalities for lesion detection, staging, and follow-up in patients with known or suspected NEN include CT enterography (CTE), MR enterography (MRE), as well as PET/CT using a somatostatin receptor analog. FDG PET/CT may have a role in the evaluation of poorly differentiated NENs. Liver MRI, ideally with a hepatocyte-specific contrast agent, should be used when in the evaluation of hepatic metastases. Imaging informs decisions regarding both surgical approaches as well as systematic therapy (specifically, peptide receptor radionuclide therapy). This AJR Expert Panel Narrative Review describes the multimodality imaging features of small bowel NENs; explores the optimal imaging modalities for their diagnosis, staging, and follow-up; and discusses how imaging may be used to guide therapy.