Accuracy of 18F-Fluorocholine PET for the Detection of Parathyroid Adenomas: Prospective Single-Center Study

Abstract

The purpose of this prospective study was to determine the correct localization rate (CLR) of 18F-fluorocholine PET for the detection of parathyroid adenomas in comparison to 99mTc-sestamibi imaging. Methods: This was a single-arm prospective trial. Ninety-eight patients with biochemical evidence of primary hyperparathyroidism were imaged before parathyroidectomy using 18F-fluorocholine PET/MRI. 99mTc-sestamibi imaging performed separately from the study was evaluated for comparison. The primary endpoint of the study was the CLR on a patient level. Each imaging study was interpreted by 3 masked readers on a per-region basis. Lesions were validated by histopathologic analysis of surgical specimens. Results: Of the 98 patients who underwent 18F-fluorocholine PET, 77 subsequently underwent parathyroidectomy and 60 of those had 99mTc-sestamibi imaging. For 18F-fluorocholine PET in patients who underwent parathyroidectomy, the CLR based on the masked reader consensus was 75% (95% CI, 0.63-0.82). In patients who underwent surgery and had an available 99mTc-sestamibi study, the CLR increased from 17% (95% CI, 0.10-0.27) for 99mTc-sestamibi imaging to 70% (95% CI, 0.59-0.79) for 18F-fluorocholine PET. Conclusion: In this prospective study using masked readers, the CLR for 18F-fluorocholine PET was 75%. In patients with a paired 99mTc-sestamibi study, the use of 18F-fluorocholine PET increased the CLR from 17% to 70%. 18F-fluorocholine PET is a superior imaging modality for the localization of parathyroid adenomas.

Keywords: PET; endocrine; fluorocholine; hyperparathyroidism; parathyroid adenomas.

© 2021 by the Society of Nuclear Medicine and Molecular Imaging.

Figures

Graphical abstract

FIGURE 1.

STARD flow diagram for efficacy cohort.

FIGURE 2.

Example patient who underwent both 18F-fluorocholine PET and 99mTc-sestamibi imaging. (A–C) 18F-fluorocholine PET was correctly localized by all 3 readers as positive on both right (solid arrows) and left (dotted arrow). (D–F) 99mTc-sestamibi imaging study (which included immediate and 2-h SPECT, although only 2-h is shown) was called negative by all 3 readers. At parathyroidectomy, both lesions seen on 18F-fluorocholine PET were confirmed to be parathyroid adenomas. A = PET maximum-intensity projection (MIP); B = PET axial; C = PET fused; D = SPECT MIP; E = SPECT axial; F = fused SPECT.