Primary hyperparathyroidism is characterized by hypercalcemia and hypophosphatemia due to excess of parathyroid hormone, which results in bone disease, recurrent renal stone, peptic ulcer and pancreatitis. Primary hyperparathyroidism is also known to be associated with previous or concurrent neoplasms. In addition, there are several reports that primary hyperparathyroidism is also associated with an increased risk of developing malignancies even after parathyroidectomy. However, no domestic reports have been made about the neoplasm after parathyroidectomy due to primary hyperparathyroidism in the literature. Here, we report a case of colon cancer which was found eight years after the resection of parathyroid adenoma, which was detected during the treatment of prolactinoma. [Korean Journal of Bone Metabolism, 16(2): 119-124, 2009]
