Endocrine Abstracts

We report a case of malignant hemangiopericytoma in sellar region in a 73-year-old lady who initially presented with symptomatic hyponatraemia. She was found to have hypocortisolism on short synacthen test. She was treated with hydrocortisone and was found to have secondary hypothyroidism. Her gonadotropin levels were commensurate with menopause, prolactin levels were normal and there was no suggestion of diabetes insipidus. Initial pituitary magnetic resonance imaging (MRI) was normal. Ten months after the initial presentation, she developed bi-temporal visual field deficits, and repeat imaging revealed a large sellar mass compressing the optic chiasm. She underwent emergency endoscopic endonasal resection. Histopathology was consistent with malignancy haemangiopericytoma (WHO Grade III). She had residual tumour on repeat imaging and underwent intensity modulation radiotherapy allowing high precision delivery of radiation to the tumour avoiding nearby structures. Her repeat MRI seven months after surgery suggests stable appearances, and she is on thyroxine, hydrocortisone and desmopressin replacement. Haemangiopericytomas are rare mesenchymal tumours arising from pericytes of the capillaries and can happen anywhere in the body. Sellar and parasellar malignant haemangiopericytomas are exceedingly rare with only a few cases reported worldwide. They can present with mass effects like headache or visual symptoms or symptoms of hypopituitarism. They often mimic pituitary adenomas on imaging. There are no guidelines available for the optimal management of these tumours as they are rare. They are very aggressive tumours that tend to recur and metastasize, even after complete resection, therefore postoperative radiotherapy is essential.