A rare case of parathyroid cyst mimicking thyroid nodule: clinical, imaging, and pathological insights

Parathyroid cysts are rare lesions that can be misdiagnosed as thyroid nodules due to overlapping clinical and imaging features. This case report describes a parathyroid cyst in a 42-year-old male, presenting with hoarseness and dysphagia, emphasizing the importance of accurate diagnosis and surgical management. A 42-year-old male was incidentally found to have a right thyroid nodule during a routine health check. He presented with hoarseness and a sensation of food sticking in the throat.Ultrasound showed a mixed cystic and solid nodule in the right thyroid lobe, measuring 72 × 34 mm. CT imaging revealed a well-defined, low-density cystic lesion extending into the superior mediastinum, displacing the trachea and esophagus, measuring 4.5 × 7.2 × 3.2 cm. Preoperative parathyroid hormone (PTH) levels were elevated at 79.5 pg/ml. The patient underwent complete surgical excision of the mass on July 3, 2024. Intraoperative findings confirmed a cystic mass posterior to the right thyroid lobe, largely extending retrosternally. Postoperative pathology confirmed a benign parathyroid cyst, and the patient experienced significant improvement in voice and swallowing postoperatively. Careful differentiation between parathyroid cysts and thyroid nodules is crucial, as imaging and clinical features can overlap. Accurate diagnosis and complete surgical excision are essential for effective management.