18F-Choline PET/CT scan for localizing Parathyroid Adenoma in patients with Primary hyperparathyroidism

Background Materials and Methods This retrospective single-center study included patients with biochemically confirmed PHPT who underwent 18F-choline PET/CT between 2022 and 2025 after inconclusive or discordant conventional imaging. Only patients who subsequently underwent parathyroidectomy with histopathological confirmation of parathyroid adenoma were included. Histopathology served as the reference standard. Localization findings from ultrasonography, 99mTc-MIBI SPECT/CT, and 4D-CT were compared with surgical and histopathological findings. Results A total of 164 patients underwent 18F-choline PET/CT during the study period. Ninety-four patients were excluded because histopathological confirmation was unavailable (n = 92), parathyroid carcinoma was diagnosed (n = 1), or familial hypocalciuric hypercalcaemia was present (n = 1). Seventy patients met the inclusion criteria. Fifty-nine patients (84%) were female, with a median age of 54 years (range, 24–78 years). All 70 patients included in the study had positive 18F-choline PET/CT findings that corresponded to surgically confirmed parathyroid adenomas. Among these patients, ultrasonography correctly localized the adenoma in 27 of 60 patients (45%), 99mTc-MIBI SPECT/CT in 11 of 34 patients (32%), and 4D-CT in 15 of 22 patients (68%). Conclusion In this cohort of surgically treated patients with biochemically confirmed PHPT and inconclusive or discordant first-line imaging, 18F-choline PET/CT demonstrated positive localization in all included cases with histopathologically confirmed parathyroid adenomas. These findings support the value of 18F-choline PET/CT as a second-line localization modality in selected patients. However, because only patients with positive PET/CT findings who underwent surgery were included, the study was not designed to determine the sensitivity, specificity, or predictive values of 18F-choline PET/CT.