Quantitative 18F-DOPA PET/CT in pheochromocytoma: the relationship between tumor secretion and its biochemical phenotype

Abstract

This retrospective study shows a correlation between F-FDOPA uptake, especially using TL uptake, urinary MNs, and a PHEO biochemical phenotype. This illustrates that beyond its localization value,F-FDOPA PET further enables PHEO characterization at a specific metabolic level.

18F-FDOPA PET/CT Uptake Parameters Correlate with Catecholamine Secretion in Human Pheochromocytomas

“…However, there is still no consensus concerning the best predictive 18 F-FDOPA PET/CT uptake parameter to be used in clinical practice. Like ours, the recent study published by Amodru et al [9] was a retrospective and single-center trial. In their study, 56 patients with a median age of 47.5 years were included.…”

“…While only a few studies have been pub- lished on the topic, some similar observations have been made by others in the past [9,18,19]. However, there is still no consensus concerning the best predictive 18 F-FDOPA PET/CT uptake parameter to be used in clinical practice.…”

“…Interestingly, significant positive correlations were observed between the value of urinary MN and MTV 42% and total lesion uptake, respectively, a result close to the one observed in our study with the MB. The study by Amodru et al [9] showed that the SUV max of PHEO correlates with the concentration of circulating catecholamines, whereas Imani et al [19] did not find any statistically significant correlation between the SUV max of PHEO and the corresponding biochemical markers. This discrepancy could be due to the SUV max parameter itself, which is subject to many sources of variability that are not controlled or even taken into account in most reported studies and which reflects a single-pixel value [20,21].…”

“…The principle of 18 F-FDOPA PET/CT is based on the property of neuroendocrine tumor cells to take up L-DO-PA via the neutral amino acid transporter system L (LAT1 or LAT2), to decarboxylate it into dopamine thanks to amino acid decarboxylase, and to eventually store amino acids (such as DOPA) and their biogenic amines in vesicles [8]. A recent study suggests a positive correlation between the intensity of 18 F-FDOPA uptake in patients with PHEO and their respective level of urinary MN [9]. However, the relation between the 18 F-FDOPA PET/CT uptake parameters and the cellular pattern of catecholamine secretion in the corresponding tumors may need further clarification and new insights.…”

Exploring the link between tumour metabolism and succinate dehydrogenase deficiency: A 18F‐FDOPA PET/CT study in head and neck paragangliomas

“…2 In the setting of PPGL, 18 F-fluorodeoxyglucose ( 18 F-FDG) avidity was found to be associated to SDHx mutations, 3-6 possibly due to the effects of succinate on stabilization of hypoxia-inducible factors 7 and/or on microenvironment metabolism. 11,12 However, beyond secretion, patients with certain genetic mutations have been found as an important component of 18 F-FDOPA phenotype since false-negative findings are mainly observed in patients with metastatic SDHx-PPGL. 18 F-FDOPA PET/CT was found to be a sensitive imaging tool for sporadic and SDHx-related HNPGL (mostly linked to SDHD mutations).…”