68ga-dotanoc and Abdominal-Neoplasms

To evaluate Ga-DOTANOC positron emission tomography/computed tomography (PET/CT) and I-meta-iodobenzylguanidine single-photon emission computed tomography/computed tomography (131I-MIBG SPECT/CT) in patients with paragangliomas, including uncommon primaries.. Ninety patients were prospectively enrolled, and both scans were done within 2 weeks of each other. Lesions were grouped as Head/neck, abdominal, uncommon primary paraganglioma, and metastatic lesions. In most histopathology was used as reference standard.. PET/CT had sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 97%, 94%, 99%,88%,97% respectively on patient wise analysis (90) and 98%, 94%, 99%, 85% and 97% respectively on lesion wise analysis (149). Comparison with MIBG SPECT/CT: Significant difference in sensitivities noted (PET/CT-98%, I-131 MIBG -39%) (P < 0.001), however, no significant difference in specificities (94% and 100%, respectively). Group-wise analysis: Head/Neck: Significant difference noted between PET/CT (sensitivity 100%) and I-131 MIBG SPECT/CT (sensitivity 22%) (P = 0.001). Abdominal: No significant difference noted in sensitivities and specificities of PET/CT and I-131 MIBG SPECT/CT. Uncommon paraganglioma: PET/CT detected 10 of 11, while I-131 MIBG detected only 2 of 11 uncommon paraganglioma. Metastatic sites: Significant difference noted between PET/CT (sensitivity 97%) and I-131 MIBG SPECT/CT (sensitivity 33%) (P < 0.0001).. The study demonstrates high diagnostic accuracy of Ga-DOTANOC PET/CT and superiority over I MIBG SPECT/CT for evaluation of extra-adrenal paraganglioma. The current diagnostic role of I-131 MIBG seems limited to abdominal paragangliomas and for theranostic purpose.

Topics: 3-Iodobenzylguanidine; Abdominal Neoplasms; Adolescent; Adult; Aged; Child; Female; Head and Neck Neoplasms; Humans; Male; Middle Aged; Organometallic Compounds; Paraganglioma; Positron Emission Tomography Computed Tomography; Prospective Studies; Sensitivity and Specificity; Single Photon Emission Computed Tomography Computed Tomography; Young Adult

Topics: Abdominal Neoplasms; Dihydroxyphenylalanine; Head and Neck Neoplasms; Humans; Hypertension; Image Processing, Computer-Assisted; Mutation; Organometallic Compounds; Paraganglioma; Peptides; Positron Emission Tomography Computed Tomography; Succinate Dehydrogenase

Pheochromocytomas/paragangliomas are somatostatin receptor 2-overexpressing tumors. Ga-DOTA-peptide imaging has recently shown excellent results in the detection of metastatic lesions in these tumors. However, currently used Ga-DOTA peptides show different somatostatin receptor affinities. Here, we report the remarkable differences in a patient who was imaged with Ga-DOTANOC and Ga-DOTATATE PET/CT within a 7-month period. The patient presented with a nearly negative Ga-DOTANOC PET/CT scan, whereas on Ga-DOTATATE PET/CT, multiple highly positive lesions were identified.

Topics: Abdominal Neoplasms; Child; Female; Humans; Lung Neoplasms; Neoplasm Metastasis; Organometallic Compounds; Paraganglioma; Positron Emission Tomography Computed Tomography; Protein Binding; Radiopharmaceuticals; Receptors, Somatostatin; Succinate Dehydrogenase