A novel imaging approach in hyperparathyroidism: [68Ga]Ga-Trivehexin PET/CT

To evaluate the diagnostic performance of [68Ga]Ga-Trivehexin PET/CT for localizing hyperfunctioning parathyroid tissue in patients with primary hyperparathyroidism (PHPT) and to compare it with [99mTc]Tc-MIBI scintigraphy with SPECT/CT (MIBI scan).

In this retrospective study, patients with biochemically confirmed PHPT underwent both MIBI scan and [68Ga]Ga-Trivehexin PET/CT. Patient- and lesion-based detection rates were compared between modalities. [68Ga]Ga-Trivehexin PET/CT was acquired at approximately 40 ± 20 min after injection; delayed imaging at 80 ± 20 min was performed in a subset. Dynamic PET imaging was performed in three patients. Quantitative parameters, including SUVmax and lesion-to-background ratios, were recorded. Clinically relevant subgroups, including MEN-1-associated PHPT and persistent disease after surgery, were assessed.

A total of 50 parathyroid-related lesions were evaluated in 38 patients. On patient-based analysis, MIBI scan and [68Ga]Ga-Trivehexin PET/CT correctly localized hyperfunctioning parathyroid tissue in 28 of 38 (74%) and 35 of 38 (92%) patients, respectively. On lesion-based analysis, [68Ga]Ga-Trivehexin PET/CT detected 49 of 50 lesions (98%), compared with 29 of 50 lesions (58%) detected by MIBI scan (P < 0.05). [68Ga]Ga-Trivehexin PET/CT demonstrated distinct focal uptake in 18 lesions with negative or equivocal MIBI findings. Dual-time-point imaging showed no significant differences in lesion SUVmax or lesion-to-background ratios between early and delayed scans. Dynamic imaging demonstrated a rapid increase in lesion contrast followed by a plateau, with no consistent improvement beyond approximately 25 min.

[68Ga]Ga-Trivehexin PET/CT demonstrated higher detection rates than MIBI scan for localizing hyperfunctioning parathyroid tissue in PHPT, particularly in multiglandular and subcentimetric disease. Early acquisition appears sufficient, with limited added value of delayed imaging.