Usefulness of 18F-fluorocholine PET/CT for preoperative localization of parathyroid adenomas

Objectives Accurate localization of parathyroid adenomas allows use of minimally invasive surgical techniques. Some PET tracers may be clinically useful to image parathyroid adenomas with advantage of superior image resolution and mechanism of uptake not affected by P-glycoprotein expression. Aim: to assess usefulness of 18F-fluorocholine PET/CT for preoperative localization of parathyroid adenomas.

Methods In 11 patients with clinical primary hyperparathyroidism (elevated Ca2+ and iPTH) 99mTc-sestaMIBI SPECT (600 MBq) and 18F-fluorocholine (100MBq) were performed. Intraoperative localization and histology were used as gold standard for comparison of diagnostic performance of both imaging techniques.

Results 15 adenomas were found intraoperatively and confirmed histologically. 18F-fluorocholine correctly localized 11/15 adenomas (73%) and the affected side in 13/15 adenomas (87%). 99mTc-sestaMIBI SPECT only localized adenomas in 5/15 cases (33%) and the affected side in 6/15 cases (40%). Moreover, 18F-fluorocholine PET/CT correctly localized 2/2 adenomas occurring in one patient and 3/4 hyperplastic glands in another patient with hyperplasia.

Conclusions Although this initial clinical sample is small, 18F-fluorocholine PET/CT appears to be clearly superior to 99mTc-sestaMIBI SPECT for localization of parathyroid adenomas, especially in cases of multiple localizations. Further study is needed to confirm our initial results.