Endocrine Abstracts

Introduction: Parathyroid cysts (PCs) are uncommon lesions. They represent less than 0.5% of parathyroid lesions. Cysts are divided into two groups, functional and non-functional, in relation to their hormonal characteristics. Non-functioning ones make up 80 – 90% of PCs.We discussed three cases of non-functioning parathyroid cysts that we surgically excised.

Methods: We report 3 cases of non-functioning PCs treated in our department.

Results: Our series included 1 man and 2 women. The median age was 35 years [22 years – 45 years]. Patients presented a neck lump in the lower anterior neck. Dysphagia was noted in 2 cases. Clinical examination showed a soft, non-tender and well-limited anterior neck mass that move on swallowing. The mass had a median approximate size of 3 cm.Ultrasonography of the neck revealed a cystic lesion behind the left lobe of the thyroid gland in 1 patient and a right cystic thyroid nodule in 2 cases.Fine-needle aspiration (FNA) with detection of parathyroid hormone (PTH) in the cyst fluid was performed in one patient and the intracystic PTH level was high (355 ng/l). Recurrence was noted 1 month after the cyst aspiration. Serum calcium and PTH levels were normal in all patients.All patients underwent surgical treatment: surgical excision of the cystic mass in one case and right lobectomy in 2 cases. Histologic exam confirmed the diagnosis in all cases. PC was intrathyroidal in 2 cases.After median follow-up of 25 months [12 months - 41 months], no recurrence was noted.

Conclusion: Parathyroid cysts are extremely rare lesions. Our cases were nonfunctional parathyroid cystic lesions. FNA with detection of PTH in the cyst fluid (regardless of the level) is an important tool and confirmed the diagnosis in one patient in our study. Three therapeutic options are indicated: cyst aspiration, sclerotherapy and surgery.