A Pilot Comparison of 18F-fluorocholine PET/CT, Ultrasonography and 123I/99mTc-sestaMIBI Dual-Phase Dual-Isotope Scintigraphy in the Preoperative Localization of Hyperfunctioning Parathyroid Glands in Primary or Secondary Hyperparathyroidism

Abstract

We compared 18F-fluorocholine hybrid positron emission tomography/X-ray computed tomography (FCH-PET/CT) with ultrasonography (US) and scintigraphy in patients with hyperparathyroidism and discordant, or equivocal results of US and 123I/99mTc-sesta-methoxyisobutylisonitrile (sestaMIBI) dual-phase parathyroid scintigraphy. FCH-PET/CT was performed in 17 patients with primary (n = 11) lithium induced (n = 1) or secondary hyperparathyroidism (1 dialyzed, 4 renal-transplanted).The reference standard was based on results of surgical exploration and histopathological examination. The results of imaging modalities were evaluated, on site and by masked reading, on per-patient and per-lesion bases.In a first approach, equivocal images/foci were considered as negative. On a per-patient level, the sensitivity was for US 38%, for scintigraphy 69% by open and 94% by masked reading, and for FCH-PET/CT 88% by open and 94% by masked reading. On a per-lesion level, sensitivity was for US 42%, for scintigraphy 58% by open and 83% by masked reading, and for FCH-PET/CT 88% by open and 96% by masked reading. One ectopic adenoma was missed by the 3 imaging modalities. Considering equivocal images/foci as positive increased the accuracy of the open reading of scintigraphy or of FCH-PET/CT, but not of US. FCH-PET/CT was significantly superior to US in all approaches, whereas it was more sensitive than scintigraphy only for open reading considering equivocal images/foci as negative (P = 0.04). FCH uptake was more intense in adenomas than in hyperplastic parathyroid glands. Thyroid lesions were suspected in 9 patients. They may induce false-positive results as in one case of oncocytic thyroid adenoma, or false-negative results as in one case of intrathyroidal parathyroid adenoma. Thyroid cancer (4 cases) can be visualized with FCH as with 99mTc-sestaMIBI, but the intensity of uptake was moderate, similar to that of parathyroid hyperplasia.This pilot study confirmed that FCH-PET/CT is an adequate imaging tool in patients with primary or secondary hyperparathyroidism, since both adenomas and hyperplastic parathyroid glands can be detected. The sensitivity of FCH-PET/CT was better than that of US and was not inferior to that of dual-phase dual-isotope 123I/99mTc-scintigraphy. Further studies should evaluate whether FCH could replace 99mTc-sestaMIBI as the functional agent for parathyroid imaging, but US would still be useful to identify thyroid lesions.

High-resolution magic angle spinning 1H nuclear magnetic resonance spectroscopy metabolomics of hyperfunctioning parathyroid glands

“…30 Interestingly, recent studies have shown that 18 F-fluorocholine positron emission tomography (PET) is a very promising imaging method for localization of parathyroid adenomas. [31][32][33][34][35][36] Our results are in agreement with these observations and could represent the biologic substrate and justification to the use of 18 F-fluorocholine PET imaging in HPT. Moreover, a higher amount of succinate and fumarate was shown by network analysis within SGD compared with MGD, suggesting an increased activity of the tricarboxylic acid cycle.…”

Use of PET tracers for parathyroid localization: a systematic review and meta-analysis

“…Five recent studies published results regarding 18F-FCH; however, Michaud et al and Lezaic et al published two articles using the same population [28, 29, 37, 38]. The most recent study of Michaud et al included 17 patients without prior neck surgery, divided in 11 patients with pHPT, five with sHPT, and one lithium-associated [28].…”

“…The most recent study of Michaud et al included 17 patients without prior neck surgery, divided in 11 patients with pHPT, five with sHPT, and one lithium-associated [28]. All patients had 18F-FCH PET-CT because of negative/discordant ultrasound and 123 I/ 99m Tc-sestamibi subtraction scintigraphy.…”

PET/CT with 18 F–choline: Physiological whole bio-distribution in male and female subjects and diagnostic pitfalls on 1000 prostate cancer patients

“…Unfortunately, being the experience with radiolabeled choline PET/CT largely linked to studies developed on PC patients, few information are available on its "in vivo" bio-distribution in female patients. In fact, this radiopharmaceutical was administered in female patients only in few papers investigating parathyroid adenomas (24) or BT (25). As a matter of fact, in these last cited papers, the acquisition protocols were developed with segmental scans of brain and/or neck, not including the rest of the female body.…”