Locating hyperfunctioning parathyroid glands using ¹¹C-Choline PET/CT: an inter- and intra-observer variation study.

Area of Science:

• Nuclear Medicine
• Radiology
• Endocrinology

Background:

• 11C-Choline PET/CT is increasingly used for detecting hyperfunctioning parathyroid glands in primary hyperparathyroidism.
• Evaluating the robustness of this imaging method is crucial for determining its widespread applicability.

Purpose of the Study:

• To assess the intra- and inter-observer agreement of 11C-Choline PET/CT for parathyroid gland localization.
• To determine if the method is reader-sensitive and requires specialized centers.

Main Methods:

• PET/CT images from 40 primary hyperparathyroidism patients were analyzed by three readers (one expert, two non-experts).
• Intra- and inter-observer agreement was calculated using Fleiss' kappa method.
• Sensitivities and specificities of non-expert readers were compared against the expert reader.

Main Results:

• Good to near-perfect intra-observer agreement was achieved across all readers.
• Inter-observer agreement was good, with kappa values ≥ 0.74.
• High sensitivities (>81% for side, 75% for quadrant) and specificities (>94%) were reported, with high reader confidence in most cases.

Conclusions:

• 11C-Choline PET/CT is not reader-sensitive for localizing hyperfunctioning parathyroid glands.
• The method can be safely implemented in centers with moderate case volumes, provided cyclotron access for 11C-Choline production.
• The study adhered to ethical guidelines, including the Helsinki Declaration and ICH-GCP.