Modern possibilities of the diagnosing of primary hyperparathyroidism

Background. Currently, the most common method of preoperative imaging of affected parathyroid glands (PTG) is a combination of scintigraphy with technetium [99mTc] sestamibi and neck ultrasound (with a sensitivity of 81–95%). In some cases, such as multiple PTG lesions, their ectopic location, multiple nodular thyroid lesions, and their hyperfunction or inflammation, standard imaging methods may show negative or contradictory results, which requires the use of 2nd-line diagnostic studies. One is positron emission tomography combined with computed tomography (PET/CT) with 11C-choline.

Aim. To determine the role of PET/CT with 11C-choline in the topical diagnosis of primary hyperparathyroidism.

Materials and methods. Retrospective analysis of data from 33 patients with primary hyperparathyroidism who underwent parathyroidectomy at the Department of Surgical Endocrinology of Pavlov First Saint Petersburg State Medical University from 2022 to 2024. Due to the ineffectiveness of standard imaging and/or the persistence of primary hyperparathyroidism after the first surgery, all patients included in the study underwent PET/CT with 11C-choline (Almazov National Medical Research Centre). The accuracy, sensitivity, specificity, and positive and negative predictive values were calculated considering the pathological postoperative verification of adenoma/hyperplasia and/or achievement of the reference range of parathyroid hormone and calcium plasma levels.

Results. A total of 41 masses were removed in 33 patients (8 patients had 2 masses removed each). Thirty-seven areas were positive according to PET/CT with 11C-choline. Its diagnostic accuracy was 95.5%, sensitivity 90.2%, specificity 97.8%, positive predictive value 94.9%, and negative predictive value 95.7%.

Conclusion. PET/CT with 11C-choline demonstrated high efficacy in preoperative localization assessment of PTG adenomas, even in cases where the results of first-line imaging methods were ambiguous. We use this method in complex cases, although it can be considered an alternative to first-line imaging. This question remains open and requires further studies comparing economic feasibility.