Neuroendocrine Carcinoma of the Endometrium with Ectopic Secretion of Parathyroid Hormone Presenting as Hypercalcemia- Related Posterior Reversible Encephalopathy syndrome: A Case Report.

Purpose: Posterior reversible encephalopathy syndrome (PRES) displayed various acute neurological symptoms. PRES is a rare presentation of hypercalcemia. Here we present a case with ectopic secretion of parathyroid hormone from neuroendocrine carcinoma of the endometrium presenting as hypercalcemia-related PRES.

Case report: A 67-year-old woman presented with acute generalized tonic-clonic seizure followed by post-ictal confusion and neuropsychiatric behaviors. The diagnosis is PRES. Investigations showed uterine cervical region with multiple liver metastasis complicated with hypercalcemia, elevated intact parathyroid hormone. Further pathology concluded as a poorly differentiated adenocarcinoma of the endometrium with neuroendocrine differentiation and immunoreactive for PTH. The patient's neurologic manifestations had resolved. Serum free calcium level and intact-PTH had declined after first course of definitive chemoradiation.

Conclusion: Immunostaining of the tumor tissue can be used to estimate the ectopic PTH production within the tumor cells. Early detection and appropriate clinical treatment hold the potential to improve the prognosis of refractory hypercalcemia and hypercalcemia related PRES. Keyword: Posterior reversible encephalopathy syndrome; hypercalcemia; intact-parathyroid hormone; parathyroid hormone-related peptide; neuroendocrine carcinoma of endometrium.