18F-fluorocholine PET/MRI versus ultrasound and sestamibi for the localization of parathyroid adenomas

PurposeAccurate preoperative localization is imperative to facilitate a minimally invasive parathyroidectomy (MIP) in primary hyperparathyroidism (pHPT). This study aims to compare the diagnostic value of standard-of-care localization techniques (ultrasound [US] and (99m)Technetium (Tc-99m) -sestamibi scintigraphy) to [F-18]-fluorocholine positron emission tomography/magnetic resonance imaging (FCH-PET/MRI) to determine the additional clinical usefulness of PET/MRI in a Canadian cohort.MethodsWe conducted a prospective, appropriately powered, study to compare the diagnostic value of -FCH PET/MRI to that of the US and Tc-99m-sestamibi scintigraphy for localization of parathyroid adenomas in a patient with pHPT. The primary outcome was the per-lesion sensitivity and positive predictive value (PPV) of FCH-PET/MRI, US, and Tc-99m-sestamibi scintigraphy. Intraoperative surgeon localization, parathormone levels, and histopathological findings were used as reference standards.ResultsForty-one patients underwent FCH-PET/MRI of which 36 patients had parathyroidectomy. In these 36 patients, 41 parathyroid lesions were histologically confirmed as adenomas or hyperplastic glands. Per-lesion sensitivity of FCH-PET/MRI was 82.9% and of US and Tc-99m-sestamibi scintigraphy combined at 50.0%, respectively. The sensitivity of FCH-PET/MRI was superior to that of US and Tc-99m-sestamibi scintigraphy (p = 0.002). In the 19 patients in whom both US and Tc-99m-sestamibi scintigraphy were negative, PET/MRI correctly identified the parathyroid adenoma in 13 patients (68%).ConclusionsFCH-PET/MRI is a highly accurate imaging modality for localization of parathyroid adenomas in a tertiary center in North America. It is a superior functional imaging modality to Tc-99m-sestamibi scintigraphy alone and more sensitive for localization of parathyroid lesions than US and Tc-99m-sestamibi scintigraphy combined. This imaging modality could become the most valuable preoperative localization study given its superior performance in localizing parathyroid adenomas.

Automated summary

This study compared the diagnostic value of standard-of-care localization techniques to FCH-PET/MRI in primary hyperparathyroidism. The results showed that FCH-PET/MRI is a highly accurate imaging modality for localization of parathyroid adenomas and is superior to other techniques.