Poster Presentation ESA-SRB 2023 in conjunction with ENSA

MH is a 50-year-old smoker, who was referred to the emergency department with pan-hypopituitarism during work-up of increasing lethargy and recent diagnosis of a primary bronchial neoplasm on computed tomography of chest. He also reported erectile dysfunction, mild morning headache, blurry vision, nocturnal polyuria and polydipsia. Thyroxine 50 microg daily was started by his GP 2 weeks prior to his presentation. Planned bronchoscopy was postponed and endocrinology was consulted. His blood pressure was 102/65 mmHg without postural drop, otherwise clinical examination was unremarkable.

He received empirical intravenous hydrocortisone 100 mg intravenously awaiting cortisol levels. Diabetes insipidus was suspected clinically despite a normal serum sodium, with good clinical response to 200mcg of desmopressin. Desmopressin was subsequently withheld then reduced to 100mcg daily due to initial hyponatraemia. Thyroxine was continued.

Results of his anterior pituitary hormone panel are shown in Table 1 and table 2.

Pituitary metastases are rare. Diabetes insipidus and opthalmoplegia are associated with pituitary metastases¹. Clinical presentation of pituitary metastases varies. Patients with pituitary metastases and hypophysitis can present with headaches and hypocortisolism. However, pituitary metastases are associated with diabetes insipidus and opthalmoplegia. Adrenal insufficiency is the most common in patients with pituitary metastases, followed by central hypothyroidism, hyperprolactinaemia and diabetes insipidus¹. MH’s clinical features were consistent with pituitary metastasis and a biopsy was not indicated. In this case, diabetes insipidus was suspected clinically despite a normal serum sodium, raising the possibility of secondary adrenal insufficiency masking the hypernatraemia associated with central diabetes insipidus. Treatment of pituitary metastases should be individualised and aim of treatment include management of the primary tumour and relieve of symptoms from mass effect with surgical resection and/or radiation therapy or comfort measures. Overall survival of patients with pituitary metastases is poor and depends on the disease burden of the primary malignancy.