The Joint Annual Scientific Meetings of the Endocrine Society of Australia and the Society for Reproductive Biology 2018

Not always as easy as ‘αβC’: A case of phaeochromocytoma with challenging pre-operative preparation (#250)

Angela McPhee 1 , Thora Chai 1 , Teresa Lam 1
  1. Diabetes and Endocrinology, Westmead Hospital, Sydney, NSW, Australia

A 55-yo woman presented with a left incidentaloma detected while being investigated for secondary causes of hypertension. She has 10-year history of hypertension controlled with olmesartan and hydrochlorothiazide with occasional hot flushes since menopause 3 years ago. She did not have any weight loss, night sweats, palpitations or diarrhoea. Examination revealed a BP of 138/79mmHg and HR 53 bpm. Initial investigations did not suggest any hormonal hypersecretion. A CT scan confirmed a 22mm adrenal lesion with pre-contrast Hounsfield measurement of 39 and avid enhancement on the arterial phase. The washout ratios were not consistent with a typical adrenal adenoma. An MRI confirmed a 20x16x16mm circumscribed solid left adrenal mass. Approximately 18 months later, biochemistry became elevated: 24-hour urinary assay for normetanephrines was 3.1 mmol/day (<2.3) and metanephrines was 0.5 mmol/day (<1.7). Plasma normetanephrine was 1400 pmol/L (<920) and plasma metanephrine was 140 pmol/L (<447). She was referred for a laparascopic adrenalectomy and was admitted 10 days pre-operatively. Despite routine alpha and beta blockade, with escalation of phenoxybenzamine doses up to 30mg TDS (1.7mg/kg) and propranolol 20mg BD, her SBP remained elevated at 140-160 mmHg. Surgery was delayed and amlodipine 10mg was added. However, despite initial response, she continued to have SBP elevations up to 150mmHg associated with palpitations. She required the addition of verapamil 40mg, with a reduction in BP to 117/80 mmHg and surgery proceeded. Her left adrenal gland was resected via laparoscopic approach. Histopathology revealed a well circumscribed, round, solid nodule measuring 22x17x18mm. Microscopic examination showed features consistent with phaeochromocytoma, with positive chromogranin and synaptophysin staining and clear margins with no vascular or perineural invasion. She is being followed up with regular screening of plasma metanephrines.