A 69-year-old male patient with the symptoms of cough and severe dysphagia for 10 months was referred to our department. Contrast-enhanced computed tomography showed a well-circumscribed retroesophageal mediastinal cystic lesion located between the C5-T5 spine with 58×32-mm in axial diameter. Preliminary diagnosis was a bronchogenic or esophageal duplication cyst (Figure 1a-c). Endoscopic ultrasonography revealed a totally anechoic and cystic submucosal lesion without calcification and septation originating from the muscularis propria at the thoracic inlet level. A written informed consent was obtained from the patient and right thoracotomy was performed. Mucoid and hemorrhagic liquid was aspirated during dissection and lesion was totally excised (Figure 2). Histopathological examination result was reported as a cystic parathyroid adenoma. The patient was discharged on postoperative Day 5 without any complication. In conclusion, ectopic parathyroid adenomas are usually located in the anterior mediastinum; however, rarely, they can be seen in the posterior mediastinum. When they are located in the posterior mediastinum, it may be challenging to distinguish them from bronchogenic cysts or esophageal duplication cysts.

Figure 1: (a) Axial, (b) coronal, and (c) sagittal view of lesion on thoracic computed tomography.

Figure 2: An intraoperative view of lesion.

Declaration of conflicting interests
The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Funding
The authors received no financial support for the research and/or authorship of this article.

References

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