Modern Nuclear Imaging for Paragangliomas: Beyond SPECT

Abstract

Learning Objectives: On successful completion of this activity, participants should be able to describe (1) the best nuclear imaging procedures to detect pheochromocytomas/paragangliomas according to the clinical situation (e.g., sporadic vs. hereditary; primary vs. metastatic; sympathetic vs. parasympathetic) and (2) the differences in the phenotypic information obtained by various PET tracers.Financial Disclosure: The authors of this article have indicated no relevant relationships that could be perceived as a real or apparent conflict of interest. CME Credit: SNM is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to sponsor continuing education for physicians. SNM designates each JNM continuing education article for a maximum of 1.0 AMA PRA Category 1 Credit. Physicians should claim only credit commensurate with the extent of their participation in the activity.For CE credit, participants can access this activity through the SNM Web site (http://www.snm.org/ce_online) through February 2013.Paragangliomas are rare neuroendocrine tumors that may arise anywhere along the paraganglial system, with a high frequency of hereditary forms or multifocal disease. Most often, paragangliomas are benign and progress slowly, but metastases may occur in about 10% of patients. In this respect, nuclear imaging in combination with anatomic imaging may be required to fully delineate the extent of the disease. PET has been increasingly used in imaging paraganglioma, paralleled by great efforts toward the development of new tracers. Recent data indicate that the choice of PET tracers should be tailored to tumor localization and to the patient's genetic status. This article provides insight into the many PET radiotracers that are currently available and others that are still only under research and guides clinicians toward appropriate use in relation to genetic carrier status. In addition, this article provides nuclear medicine physicians with the background knowledge required for understanding relationships between imaging phenotypes and molecular genetics.

Targeting Neuropeptide Receptors for Cancer Imaging and Therapy: Perspectives with Bombesin, Neurotensin, and Neuropeptide-Y Receptors

“…These new analogs also provided encouraging results in pheochromocytomas and paragangliomas (Fig. 1B) (4). Also of importance in NETs is the incretin receptor family.…”

68Ga-DOTANOC PET/CT for Baseline Evaluation of Patients with Head and Neck Paraganglioma

“…The baseline evaluation of HNPs is usually performed with CT or MR imaging to define the location and extent and to detect synchronous HNPs (9). Functional imaging is probably not necessary in the preoperative work-up of patients with negative genetic testing (9).…”

“…Radioisotope imaging with 123 I-/ 131 I-metaiodobenzylgunanidine ( 123 I-/ 131 I-MIBG) or 111 In-diethylenetriamine-pentaacetic acid (DTPA)-pentetreotide with SPECT or SPECT/CT is useful for whole-body screening in the case of metastatic or familial paragangliomas (9). The sensitivity of 123 I-/ 131 I-MIBG imaging is lower in extraadrenal paragangliomas, metastatic paragangliomas, and recurrences.…”

Semiquantitative 123I-Metaiodobenzylguanidine Scintigraphy to Distinguish Pheochromocytoma and Paraganglioma from Physiologic Adrenal Uptake and Its Correlation with Genotype-Dependent Expression of Catecholamine Transporters

“…Several studies have shown that the sensitivity of 123 I-MIBG scintigraphy is lower in extraadrenal PPGLs (33,40). Saveanu et al (37) reported a higher NET expression in adrenal than extraadrenal PPGLs, which has also been shown to be the case for VMAT-1 expression (35).…”