The Utility of 18F-Fluorocholine PET/CT in The Imaging of Parathyroid Adenomas

Abstract Aim: to estimate sensitivity of 18F-FCH PET/CT in preoperative localisation of hyperfunctioning parathyroid glands in patients with primary hyperparathyroidism (PHPT). Methods: 65 consecutive patients with PHPT who underwent neck ultrasound (US) and 99mTc/99mTc-MIBI dual-phase parathyroid scintigraphy were prospectively enrolled. Twenty-two patients had unsuccessful parathyroid surgery prior to the study. PET/CT scans were performed 65.0 ± 13.3 min after injection of 218.5 ± 31.9 MBq of 18F-fluorocholine (FCH). Three experienced nuclear medicine physicians assessed the detection rate of hyperfunctioning parathyroid tissue. Response to parathyroidectomy and clinical follow-up served as a reference test. Per-patient sensitivity and positive predictive value (PPV) were calculated for patients who underwent surgery.Results: 18F-FCH PET/CT was positive in 61 patients, and negative in four. US and parathyroid scintigraphy showed positive and negative results in 20 , 45 and 17, 48, respectively. US showed nodular goiter in 31 patients and chronic thyroiditis in 9 patients. Parathyroid surgery was performed in 43 (66%) patients. 18F-FCH PET/CT yielded sensitivity of 100% (95% CI [87.99-100]) and PPV of 85.7% (95% CI [70.77-94.06]). Similar values were observed in patients with chronic thyroiditis, nodular goiter, and patients after an unsuccessful parathyroid surgery. PET/CT identified hyperparathyroidism complications (kidney stones, osteoporotic bone fractures and brown tumours) in 11 patients.Conclusions: 18F-FCH PET/CT effectively detected hyperfunctioning parathyroid tissue and its complications. The method showed excellent sensitivity and positive predictive value, including patients with nodular goiter, chronic thyroiditis and prior unsuccessful parathyroidectomy. PET/CT performance was superior to neck ultrasound and parathyroid scintigraphy.