Clinical and surgical aspects of double adenoma in patients with primary hyperparathyroidism.

The incidence of double parathyroid adenoma in 277 prospectively documented patients suffering from primary hyperparathyroidism was 5.4 per cent (15 patients). Patients with double adenoma were all symptomatic and had a significantly higher parathyroid hormone (PTH) level and tumour weight than those with a solitary adenoma or four-gland hyperplasia. In 11 patients the adenomas were located bilaterally. Bilateral neck exploration must be performed routinely to deal successfully with this condition at initial operation. In six patients one enlarged gland was found in the thymus or posterior mediastinum. These locations should be explored, especially in patients with high PTH levels, in those in whom all four parathyroid glands cannot be detected or if only one small adenoma is found. In all such patients, selective resection of the enlarged parathyroid glands resulted in normocalcaemia (median follow-up 3.5 years). Selective resection of the pathological glands is the treatment of choice.