In one study of 138 patients with PTH-rP-mediated hypercalcemia, NEC was present in only 2.2% of cases [2]. Therefore, other causes of hypercalcemia must be considered when a patient has NEC, including hyperparathyroidism from multiple endocrine neoplasia (MEN) type 1 and local factors secreted by bone tumors [10]. Nonetheless, NEC as a cause for HHM is possible and herein we describe a case of a 31-year-old patient with HHM associated with elevated PTH-rP. This evidence concerns the gene PTH and multiple endocrine neoplasia type 1.