Benign parathyroid cyst causing vocal fold paralysis: a case report and review of the literature

Parathyroid cysts are uncommon, frequently asymptomatic lesions of the neck and superior mediastinum. Symptomatic parathyroid cysts are very rare, with roughly only 200 cases reported in the literature. Of these, only nine cases have been reported with recurrent laryngeal nerve (RLN) paralysis

We report a case of a 49-year-old man initially seen with a 6-month history of worsening hoarseness. Physical examination revealed a palpable 3-cm, firm, smooth, nontender mass of the right thyroid lobe. Fiberoscopic laryngoscopy showed right vocal cord immobility consistent with RLN paralysis. After CT and fine-needle aspiration of the mass, the patient underwent a right thyroid lobectomy. During surgery, the recurrent laryngeal nerve was found to be stretched and adherent to a right inferior lobe mass.

Histologic analysis of the surgical specimen revealed a benign parathyroid adenomatous cyst. Postoperatively, the patient's voice improved markedly. This case represents an extremely rare return of function of the RLN after cyst removal.

Parathyroid cysts should be included in the differential diagnosis for vocal fold paralysis.