Estimation of parathyroid hormone level in patients with primary hyperparathyroidism (PHPT) and negative SPECT scans in the material obtained during fine needle aspiration biopsy (FNAB) of the focal neck lesions
Zbigniew Adamczewski1, Marek Dedecjus2, Jan Brzezinski2 & Andrzej Lewinski1
Objective: The presence of a single parathyroid adenoma is a cause of primary hyperparathyroidism in most cases. Minimally invasive parathyreoidectomy is a treatment of choice in PHPT patients and precise localization of the changed parathyroids is crucial for successful removal.
The aim of the study was to assess usefulness of parathormone level estimation in the material obtained during FNAB of the focal neck lesions in order to differentiate structures such as enlarged parathyroid glands from other focal lesions in patients with HPTH and negative SPECT scans.
Design: Eighteen female patients with elevated PTH levels (range: 160617 pg/ml, median, 224 pg/ml), coexisting calcium and phosphate disorders typical for PHPT and negative SPECT scans, were prospectively evaluated. Patients age range was from 6 months to 76 years old (median, 51 years). All patients underwent ultrasound examination (Toshiba Aplio XG, 14 MHz transducer). 23 focal changes were qualified for FNAB (the volume range was from 0.1 cm3 to 3.0 cm3, median: 0.85 cm3). After FNAB examination the needle was washed out with 1 cm3 of 0,9% NaCl and PTH level was measured in the obtained material.
Results: PTH levels exceeded 5000 pg/ml in 13 patients and were lower than serum PTH levels in the remaining group (range 2435 pg/ml, median, 29 pg/ml). Patients with elevated PTH levels were offered minimally invasive surgical intervention. In all operated cases parathyroid adenoma was removed. In 2 cases neck revision modified by PTH level determinating method of the suspected lesions intraoperatively - was performed and retrotracheal parathyroid glands were removed.
Conclusions: PTH level determination in the needle wash-out obtained during FNAB has demonstrated 100% specifity in differentiating parathyroid and nonparathyroid tissues.
Identification of parathyroid lesions using described procedure is a timesaving and cost-cutting method. Negative-PTH value should suggest further need for diagnostic imaging or applying modifications while performing the surgery.