A case of papillary carcinoma of the thyroid associated with parathyroid adenoma without hyperparathyroidism.

A rare occurrence of the association of parathyroid adenoma in a case of thyroid papillary carcinoma is described. The patient was incidentally found to have parathyroid adenoma which was preoperatively diagnosed to be a metastatic lymph node. Analysis of her serum obtained before operation showed an elevation of serum parathyroid hormone (PTH) concentration without hypercalcemia. Since the association of hyperparathyroidism is high in patients with thyroid diseases, examination of not only serum levels of calcium and PTH but also careful interpretation of computed tomography (CT) and/or nuclear magnetic imaging (MRI) is necessary in the diagnosis of co-existing asymptomatic hyperparathyroidism.