Mediastinal parathyroid adenoma detected on a routine chest X-ray.

A case is described in which a large tumour was detected in the posterior mediastinum on a routine chest X-ray. Although the parathormone level was very high, no clinical nor radiographic signs of hyperparathyroidism were present. The tumour was removed by lateral thoracotomy and proved to be a parathyroid adenoma. Postoperatively the serum calcium returned to a normal level.