Refractory Hypoglycemia from Paraneoplastic Insulin-Like growth Factor 2 Secretion in A Patient with Hepatocellular Carcinoma

Objective: Hypoglycemia due to insulin-like growth factor (IGF)-2 secretion by a tumor, referred to as non–islet cell tumor hypoglycemia, or IGF-2-oma, is a rare and serious paraneoplastic complication of malignancy. When surgical resection is not an option, studies have shown improvement of hypoglycemia with glucocorticoids. We describe the case of a patient with persistent hypoglycemia despite prolonged high-dose glucocorticoid therapy. Methods: A 22-year-old man with known metastatic hepatocellular carcinoma presented with dizziness and weakness. Initial blood glucose level was found to be 10 mg/dL. Multiple injections of 50% dextrose and continuous infusion with 25% dextrose were required to maintain normal blood glucose levels. Laboratory work-up revealed suppressed C-peptide and insulin levels with hypoglycemia and an elevated ratio of IGF-2 to IGF-1, consistent with IGF-2 secretion by the tumor. Results: Despite high-dose glucocorticoid therapy, continuous intravenous dextrose was necessary to prevent hypoglycemia. In addition, the patient's tumor progressed rapidly, and he was ultimately discharged to hospice on intravenous dextrose. Conclusion: Hypoglycemia due to IGF-2 secretion is a rare and challenging paraneoplastic complication. Cases of hypoglycemia that do not respond to glucocorticoid therapy may indicate rapid disease progression and imminent death. Abbreviation: IGF insulin-like growth factor