Paraneoplastic refractory hypercalcemia due to advanced metastatic esthesioneuroblastoma.

Esthesioneuroblastoma (ENB) is a rare malignant neoplasm arising from the olfactory neuroepithelium. ENB has no distinctive clinical picture, but often presents as chronic unilateral nasal obstruction or epistaxis. It has a long natural history; the 5-year survival rates have been estimated at 82%. A number of paraneoplastic syndromes have been described in the setting of ENB. Humoral hypercalcemia of malignancy (HHM) has never been described with ENB before. We describe a case of Kadish Stage C ENB with recurrent Hypercalcemia. The hypercalcemia became refractory to therapy and was the cause of death.