Redefining preoperative imaging-based localization of adenomas in primary hyperparathyroidism patients candidates for minimally invasive surgery.
Objective: To compare the diagnostic accuracy of [18F]-Fluorocholine (FCH) PET/CT with conventional [99mTc]Tc-MIBI scintigraphy and cervical ultrasound (USG) for the preoperative localization of hyperfunctioning parathyroid tissue (HFPT) in patients with primary hyperparathyroidism (PHPT).
Methods: This prospective study included 90 patients diagnosed with PHPT who underwent [18F]F-CH PET/CT, [99mTc]Tc-MIBI SPECT/CT and Neck USG. The diagnostic accuracy of each imaging modality was assessed using intraoperative findings and histopathological confirmation as the gold standard. The localization accuracy was evaluated based on specific quadrant detection, laterality, and ectopic gland identification. The study also explored the correlation between imaging findings and biochemical parameters, including preoperative and postoperative PTH and calcium levels.
Results: [18F]F-CH PET/CT demonstrated superior accuracy in detecting pathological parathyroid glands compared to [99mTc]Tc-MIBI SPECT/CT and USG. [¹⁸F]F-CH PET/CT correctly identified 98.9% of patients with pathological glands, with a specific location accuracy of 93.2%, 65.9% and 38.8% for [¹⁸F]F-CH PET/CT, [99mTc]Tc-MIBI SPECT/CT and USG, respectively. For ectopic adenomas, FCH PET/CT achieved an accuracy of 100% (4/4), while MIBI and neck ultrasound identified these in 50% (2/4) and 0% (0/4) of cases, respectively. In two multiglandular cases, [18F]F-CH PET/CT and [99mTc]Tc-MIBI each detected one gland in one case (50%) while USG detected none; in the other case, [18F]F-CH PET/CT and USG identified both glands (100%), and [99mTc]Tc-MIBI detected none. Significant correlations were observed between SUVmax values from [18F]F-CH PET/CT and gland size, weight, and preoperative PTH levels.
Conclusions: [18F]F-CH PET/CT outperformed conventional imaging modalities in the preoperative localization of HFPT, particularly in challenging cases such ectopic or multiglandular disease. These findings support its potential as an effective and reliable imaging tool for the management of primary hyperparathyroidism.