The Diagnostic Value of Parathyroid Hormone Washout After Fine-Needle Aspiration of Suspicious Cervical Lesions in Patients With Hyperparathyroidism

Objectives/Hypothesis: We aimed to study the diagnostic value of parathyroid hormone (PTH) concentration in the needle washout of fine-needle aspiration (FNA) compared to cytology of suspicious lesions suggestive of culprit parathyroid glands in patients with recurrent or persistent primary hyperparathyroidism (PHPT). Study Design: Retrospective review. Methods: Patients with recurrent or persistent PHPT, who were referred to one surgeon and underwent FNA of the culprit parathyroid lesion preoperatively, were included in this study. All patients underwent comprehensive neck ultrasound, and suspicious lesions underwent ultrasound-guided FNA by the same surgeon. The aspiration cytology was read by a single dedicated cytopathologist blinded to the PTH washout results. A positive cutoff value for PTH washout concentration was defined as superior to serum PTH level obtained at the same time. The final diagnosis after reoperative surgery was confirmed by the same cytopathologist. Results: Twenty-four consecutive patients were included. The mean serum PTH and calcium were 111.5 +/- 106.25 pg/mL (normal: 15-65 pg/mL) and 10.8 +/- 0.5 mg/dL (normal: 8.6-10.2 pg/mL), respectively. Twenty-two patients (91.6%) had elevated PTH washout concentrations with a positive predictive value (PPV) of 100%. Cytopathology was successful in confirming parathyroid tissue only in seven patients (29%). An adenoma was identified in 19 patients (79.1%); however, five patients (20.8%) were found to have multiglandular disease. Conclusions: An elevated PTH washout concentration can help identify culprit parathyroid gland lesions with a high PPV in patients requiring reoperative parathyroid surgery. This diagnostic technique allows for targeted surgical approach in reoperative settings, especially in patients with negative preoperative sestamibi scans.