Primary hyperparathyroidism caused by an ectopic parathyroid adenoma in an uncommon location: a case report

Primary hyperparathyroidism caused by an ectopic parathyroid adenoma in the mediastinum is a rare clinical condition. We present a 75-year-old male with primary hyperparathyroidism caused by an ectopic parathyroid adenoma in the mediastinum. This patient was initially referred to the clinic for suspected incidental hypercalcemia. Initial imaging showed two suspicious lesions: one adjacent to the thyroid gland and another in the mediastinum. Further investigations identified a sole mediastinal adenoma. The diagnosis was confirmed by normalization of parathyroid hormone levels after its surgical resection. Thoroughly diagnosing such cases can prove challenging and using a single modality such as ultrasonography, computed tomography, or nuclear imaging alone may not yield conclusive findings or can give false positive results. Our case demonstrates that a combination of several imaging modalities can lead to accurate localization of the cause of primary hyperparathyroidism. This will obviate the performance of unnecessary surgical procedures. In addition, the possibility of missing additional sources of ectopic secretions of the parathyroid hormone will be reduced.