Endocrine Abstracts

A previously fit and well 29-year-old male presented with an 8-month history of progressive facial and peripheral swelling, accompanied by generalised weakness, weight gain, nocturia and a 2 year history of left-sided abdominal pain. He was originally from Ghana and moved to the UK in 2022 with limited family support. On examination he was hypertensive (157/108 mmHg) with facial fullness, dry skin, proximal muscle weakness, conjunctival injection and haematomata at recent venepuncture sites. Abdominal examination revealed a palpable large left upper quadrant mass. Blood tests demonstrated profound hypokalaemia (2.7 mmol/l [3.5-5.3]) with a metabolic alkalosis (pH 7.49 [7.32-7.43], bicarbonate 34.8 mmol/l [22-29]). He was also thrombocytopaenic (93 × 10^9/l [150-410], had an elevated AST (68 u/l [0-41]) and HbA1 c of 55 mmol/mol [20-41]. His free T4 was low (6.3 pmol/l [10.5-24.5]) with a TSH of 1.19 mU/l [0.27-4.2]. Serum cortisol levels taken at various time points, including midnight, ranged between 1971 and 2658 nmol/l. His ACTH was elevated at 184 ng/l [<50]. Cross-sectional imaging identified a 13 cm heterogenous mass arising from the tail of the pancreas, multiple liver lesions consistent with metastases and hyperplastic adrenal glands. A diagnosis of an ectopic ACTH-secreting pancreatic neuroendocrine tumour with liver metastases and associated nephrogenic diabetes, secondary to severe hypokalaemia, was made. He was commenced on metyrapone, which was uptitrated to 500/500/750 mg, and hydrocortisone 5 mg twice a day was later added. He was also treated with spironolactone and amiloride. Pancreatic biopsy confirmed a neuroendocrine tumour with a Ki-67 of <2%. His inpatient stay was complicated by acute respiratory failure secondary to pneumocystis jirovecii pneumonia (PJP), and treatment with co-trimoxazole resulted in a drug-induced acute haemolytic anaemia. This necessitated discontinuation of co-trimoxazole and a short course of high dose prednisolone. PJP treatment was completed with oral clindamycin and primaquine. Subsequent functional imaging confirmed FDG- and DOTATATE- avidity in the pancreatic tumour but most of the liver deposits were not DOTATATE-avid. His case was reviewed in the regional hepatobiliary multidisciplinary team meeting and the tumour was deemed inoperable with no suitable targets for ablation. He was commenced on monthly lanreotide alongside his block-and-replace regimen. He reports symptomatic improvement and his HbA1 c has normalised. Follow-up imaging will be arranged in due course.