Combining 4DCT and [18F]choline PET/CT as first-line imaging in primary hyperparathyroidism patients; a one-stop shop

Primary hyperparathyroidism (PHPT) is an endocrine disorder characterized by excessive parathyroid hormone secretion, typically due to a solitary parathyroid adenoma (PA). Accurate preoperative localization is crucial for successful minimal invasive surgical management. Four-dimensional computed tomography (4DCT) is increasingly used as a first-line imaging modality due to its superior sensitivity and specificity compared to ultrasound and [99mTc]Sestamibi SPECT. Recent studies have highlighted the potential role of [18F]Choline PET/CT in PA detection. This study evaluates the feasibility of a combined [18F]Choline PET/4DCT protocol as a 'one-stop shop' imaging solution for PHPT patients.

A total of 167 patients with 217 imaging modalities were retrospectively included in the database, consisting of 33 SPECT/CT, 44 4DCT, 79 PET/CT and 61 PET/4DCT studies. Radiation dose was evaluated using dose-length-product (DLP) comparing the imaging modalities and different imaging strategies. Evaluation was also performed with the pertinent radiologists/nuclear medicine physicians and endocrine surgeons.

The PET/4DCT protocol did not have a significantly higher DLP compared to the 4DCT protocol, it did have a higher DLP compared to SPECT/CT and PET/CT. The PET/4DCT protocol had a significant lower total DLP compared to most used imaging strategies except for patients with only a PET/CT. Additionally, the combined protocol facilitated improved anatomical visualisation, supporting potential benefits for surgical planning.

This study demonstrates that [18F]Choline PET/4DCT is a promising 'one-stop shop' imaging approach for PA localisation in PHPT patients without a higher radiation dose compared to previously used imaging strategies. It does increase diagnostic accuracy, streamline patient management and optimise surgical treatment.