Image-Guided Precision Medicine in the Diagnosis and Treatment of Pheochromocytomas and Paragangliomas

Abstract

In this comprehensive review, we aimed to discuss the current state-of-the-art medical imaging for pheochromocytomas and paragangliomas (PPGLs) diagnosis and treatment. Despite major medical improvements, PPGLs, as with other neuroendocrine tumors (NETs), leave clinicians facing several challenges; their inherent particularities and their diagnosis and treatment pose several challenges for clinicians due to their inherent complexity, and they require management by multidisciplinary teams. The conventional concepts of medical imaging are currently undergoing a paradigm shift, thanks to developments in radiomic and metabolic imaging. However, despite active research, clinical relevance of these new parameters remains unclear, and further multicentric studies are needed in order to validate and increase widespread use and integration in clinical routine. Use of AI in PPGLs may detect changes in tumor phenotype that precede classical medical imaging biomarkers, such as shape, texture, and size. Since PPGLs are rare, slow-growing, and heterogeneous, multicentric collaboration will be necessary to have enough data in order to develop new PPGL biomarkers. In this nonsystematic review, our aim is to present an exhaustive pedagogical tool based on real-world cases, dedicated to physicians dealing with PPGLs, augmented by perspectives of artificial intelligence and big data.

Pheochromocytoma/Paraganglioma (PPGL): A Misdiagnosed Cause of Hypertension during Pregnancy

“…MRI is highly recommended in pregnancy [ 7 , 10 ]. The other traditional imaging techniques, such as computed tomography, radionuclide imaging (e.g., [ 123 I] and [ 131 I]-MIBG), and more recently positron emission tomography using dopamine, glucose, or somatostatin analogues ( 18 F-DOPA, 18 F-FDG, or 68 gallium) [ 13 ], are contraindicated during pregnancy due to the associated risk of fetal exposure to ionizing radiation [ 5 ].…”

The Management of Phaeochromocytomas and Paragangliomas in the Era of Precision Medicine: Where Are We Now? Evidence-Based Systemic Treatment Options and Future Cluster Oriented Perspectives

“…The use of dynamic contrast enhanced MRI (DCE-MRI) in atypical cases of adrenal masses should be taken into account as its findings may be contributory to the results of chemical shift MRI [ 33 , 34 ]. Furthermore, DCE-MRI showed to be particularly useful in the diagnosis of HNPGLs, as their early initial avid enhancement is distinctive from other cervical benign lesions [ 32 , 35 , 36 ].…”

“…PPGLs cells express on their surface different molecular targets which allow images to be obtained. These include several transporters with different capture mechanisms (Norepinephrine, glucose and amino acid transporters for 123/131 I-MIBG, 18F-FDG or 18F-DOPA respectively) or membrane surface receptors (somatostatin receptors, SSTRs, for 68GA-DOTA-SST analogs) [ 21 , 31 , 32 , 36 ].…”

“…123/131 I-MIBG are both captured by the norepinephrine transporter: 123I MIBG SPECT/CT sensitivity and specificity is extremely high for sporadic PCCs, though it dramatically decreases for PGLs (52–75%), especially for HNPGLs (18–50%) and for SDHx-related tumours [ 21 , 31 , 32 , 36 , 39 , 40 ] ( Figure 2 A–C).…”

“…18F-DOPA is a radiotracer that accumulates specifically in some PPGLs due to increased uptake by amino acid transporters: 18F-DOPA PET/CT represents the functional imaging of choice in cluster 1B and cluster 2 PPGLs, as well as in FH mutated and polycythemia-related PPGLs [ 11 , 21 , 32 , 36 ]. In these cases, if not available, I123-MIBG SPECT/CT may be considered [ 21 ].…”