Endocrine Abstracts

Background: Parathyroid lesion aspiration as a preoperative adenoma localization tool is a matter of controversy. Concerns are being raised regarding both the immediate (hematoma, infection, alterations on a subsequent histologic preparate) and long term (seeding) safety.

Objective: To evaluate safety and efficacy of parathyroid fine-needle aspiration (FNA) with parathyroid hormone (PTH) washout as a localization of parathyroid lesions in patients with primary hyperparathyroidism.

Methods: We retrospectively reviewed all parathyroid FNA procedures performed by in a tertiary referral center between 2011 and 2021. Clinical, biochemical, and imaging information as well as cytology, surgery, and pathology reports were extracted from electronic medical records.

Results: Twenty-nine hyperparathyroid patients referred to parathyroidectomy following a positive localization with FNA -PTH washout were available for review. The indications for aspiration were re-confirmation of location (13/29), mismatch between imaging modalities (6/29), intra-thyroid lesion (4/29), previous neck operation (3/29) and unknown (3/29). PTH levels from the needle wash were 2.6-112.5 times the upper limit of serum norm. No immediate procedure complications except for mild neck discomfort were documented. Among 24 patients with an available pathology report, parathyroid adenoma was identified in 22, non-adenomatous parathyroid tissue in one and thyroid tissue in one patient. No cases of hematoma or abscesses were reported by the surgeons, and no histologic alternations (hemorrhage, abscess, inflammation or capsule rupture) were reported by the pathologists. There was one case of necrosis and one case of parathyroid adenoma with fibrotic changes that may or may not be related to the FNA. Twenty-six (89.6%) of the 29 patients who underwent parathyroidectomy, were biochemically cured up to a follow-up of 41.6±34.6 months.

Conclusions: Parathyroid FNA with PTH washout was accurate and neither immediate nor surgical or preparate-related complications were demonstrated in our series. This approach might be considered in selected cases.