Unsuspected nonmedullary carcinoma of the thyroid in patients with hyperparathyroidism.

All patients with hyperparathyroidism seen in a large referral military hospital within a twenty month period underwent neck exploration by one of us (HN). Three patients were found to have an unsuspected solid thyroid nodule measuring 0.5 to 1.5 cm. All were widely excised by thyroid lobectomy and isthmectomy and found to be follicular or papillary carcinoma of the thyroid. These three patients join thirty-one previously reported clinical cases documenting an association between parathyroid adenoma and nonmedullary carcinoma of the thyroid. Because of the high potential for malignancy in this clinical setting, we urge careful examination and palpation of the thyroid gland during neck exploration for hypercalcemia in order to detect and cure "early" malignancies of the thyroid.