FDG PET is not all that sensitive in neuroendocrine cancers(NET). One study revealed that for neuroendocrine tumors, 18F-FDOPA was more accurate (sensitivity, 100%; specificity, 91%) in the detection of skeletal lesions than octreotide scintigraphy or CT but was insensitive (sensitivity, 20%; specificity, 94%) in the lung, ostensibly because of respiratory motion during image acquisition. Octreotide scintigraphy yielded its best results in the liver (sensitivity, 75%; specificity, 100%); however, it was less accurate than PET in all organs. However, 18F-FDOPA PET is less sensitive than FDG PET and standard imaging procedures for the staging of small cell lung cancer. Popperl et al recommends that 18F-FDG should be preserved for less differentiated tumors, while amine precursors and somatostatin analogs should be implemented in the diagnostic process of well-differentiated NET. NCCN on p. MS-12 does not recommend FDG PET.Kunz ET AL, Consensus Guidelines for the Management and Treatmentof Neuroendocrine Tumors. (Pancreas2013;42: 557Y577)
D. J. A. Margolis, J. M. Hoffman, R. J. Herfkens, R. B. Jeffrey, A. Quon, and S. S. Gambhir
Molecular Imaging Techniques in Body Imaging Radiology, November 1, 2007; 245(2): 333 – 356.
Becherer A, Szabo M, Karanikas G, et al. Imaging of advanced neuroendocrine tumors with (18)F-FDOPA PET. J Nucl Med 2004;45:1161–1167.
Jacob T, Grahek D, Younsi N, et al. Positron emission tomography with [(18)F]FDOPA and [(18)F]FDG in the imaging of small cell lung carcinoma: preliminary results. Eur J Nucl Med Mol Imaging 2003;30:1266–1269.
Gabriele Pöpperl PET and PET–CT in Neuroendocrine Tumors Medical Radiology, 2009, Part 5, 471-480
Katrina Ray Imaging: FDG-PET predicts neuroendocrine tumor survival Nature Reviews Clinical Oncology 7, 184 (April 2010)
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