Surgical treatment of a functional parathyroid cyst in a patient with primary hyperparathyroidism: A case report

INTRODUCTION: The frequency of parathyroid cysts in patients with primary hyperparathyroidism is from 1 to 2 %. Nowadays, parathyroid cysts remain a difficult diagnostic and therapeutic task. PRESENTATION OF CASE: A 57-year-old woman was referred to an endocrine surgeon to evaluate a presence of a mass in the left lateral region of the neck, the appearance of shortness of breath. In the biochemical analysis of the patient's blood, the serum ionized calcium level was increased - 1.53 mmol/l, parathyroid hormone − 149.6 pg/ml. Ultrasound and MSCT scan of the neck showed the presence of a fluid formation measuring 80 × 40 × 33 mm, which was displacing the trachea medially to the right. Fine-needle aspiration revealed the level of iPHT in cystic fluid >2500 pg/mL. The patient underwent cervicotomy, left lower parathyroidectomy with parathyroid cystectomy. According to a histological study, the cyst wall was presented by fibrous tissue, which was lined with epithelium from the dark main cells of the parathyroid gland. Remission of primary hyperparathyroidism was achieved. DISCUSSION: This clinical report confirms the literature on a decrease in the sensitivity of imaging methods in the diagnosis of parathyroid cysts. A decrease in the effectiveness of intraoperative monitoring of parathyroid hormone with parathyroid cysts was confirmed. CONCLUSION: With parathyroid cysts, a comprehensive assessment of all imaging methods is required. Functional parathyroid cysts require surgical treatment. Intraoperative monitoring of iPTH has low sensitivity in relation to the detection and assessment of the radicality of the operation for parathyroid cysts.