CDC73 and parathyroid gland adenoma: If the invasive features are difficult to discern, an immune profile of Ki-67 proliferation index > 5%, loss of parafibromin, loss of E-cadherin, and the expression of galectin-3 and/or protein gene product 9.5 (PGP9.5) favors carcinoma over parathyroid adenoma or atypical parathyroid tumor [5,6,7].