Recurrent Hypertensive Carcinoid Crisis Despite Somatostatin Analog Therapy

Carcinoid crisis is a rare, life-threatening complication of neuroendocrine tumors characterized by hemodynamic instability. Although hypotension is more commonly described, severe hypertension can also occur. An 84-year-old woman who had undergone resection of a grade 1 terminal ileal neuroendocrine tumor and two hepatic metastases presented with worsening flushing, severe headaches, mild wheeze, palpitations, and chest tightness. She was receiving maintenance long-acting lanreotide and had used the maximum prescribed dose of rescue subcutaneous octreotide for two weeks without sustained benefit. Her blood pressure was highly labile, with a peak systolic reading of 198 mmHg, and her heart rate reached 110 beats/min. The endocrinology team diagnosed a hypertensive carcinoid crisis. Her symptoms and hypertension resolved within 24 h of commencing a continuous intravenous octreotide infusion, and a plan was made to shorten the lanreotide dosing interval from three weeks to two weeks. Eleven days after discharge, she was readmitted with recurrent flushing, palpitations, tachycardia, and hypertension after the dose due under the revised lanreotide schedule was delayed. Subcutaneous octreotide improved the flushing and hypertension, while bisoprolol was introduced for persistent symptomatic tachycardia. Cardiac investigations showed no sustained arrhythmia or major structural abnormality. Biochemical markers measured after treatment were within their reference ranges. Subsequent somatostatin receptor positron emission tomography/computed tomography demonstrated new receptor-avid disease in the liver and left pelvis that had not been identified on preceding conventional imaging. This case demonstrates that hypertension can be the predominant hemodynamic manifestation of carcinoid crisis and highlights the limited value of normal biomarkers obtained after somatostatin analog treatment, which should not be used in isolation to exclude an acute crisis.