Table 1.

Comparison of the advantages and disadvantages of the major imaging modalities used in neuroendocrine

Modality	Advantages	Disadvantages
CT	High anatomic resolution of liver, pancreas, mesenteric lesions, abdominal/retroperitoneal lymph nodes Useful for operative planning, disease staging	High radiation exposure Optimal imaging of NETs requires IV contrast Not a functional study
MRI	Best modality to detail hepatic lesions Good pancreatic resolution No radiation exposure Gadolinium contrast is safer if renal dysfunction	Poorer resolution of GI tract, mesenteric lesions Cannot image patients with metal implants Not a functional study
Ultrasound	Useful for estimating hepatic tumor burden Inexpensive Available at the majority of institutions No radiation exposure	Study quality dependent upon the skill of the US technician Limited sensitivity if performed without microbubble contrast
Octreoscan	Functional study Level of uptake can be graded Provides whole body image Predicts response to therapy	High background in Gl tract, which may obscure midgut NETs Patient must be scanned twice in 24 h Low anatomic detail Need to hold Octreotide prior to scan
MIBG	Functional study High specificity for pheochromocytoma, paraganglioma, and glomus tumors Provides whole body image Predicts response to therapy	High background Low anatomic detail Many medications can interfere with the scan and must therefore be held Thyroid must be blocked prior to scan Patient scanned 24 h after contrast administration
FDG-PET	Good for high grade NETs Good anatomic resolution	Uptake unlikely in low-grade NETs
DOTA-PET	Functional study Uptake can be quantified Good anatomic resolution Provides whole body image Image acquired over 2 h Predicts response to therapy	Physiologic uptake in uncinate process, pituitary, spleen and kidneys may be confused for tumor uptake Need to hold Octreotide prior to scan Available at a limited number of centers in the USA