THU373 Refractory Hypoglycemia In A Patient With Metastatic Cholangiocarcinoma: Abstract

Disclosure: M.G. Fernandez: None. D.J. Selen: None. Background: Nonislet cell tumor hypoglycemia is an uncommon but severe complication of cancer. It results from tumoral overproduction of insulin-like growth factor 2 (IGF-2), which inhibits hepatic glycogenolysis and the release of glucagon and growth hormone (GH). These three mechanisms can result in severe and refractory hypoglycemia. Clinical Case: We present a case of a 57-year-old female newly diagnosed with metastatic cholangiocarcinoma who was admitted to the hospital after an episode of syncope at home in the setting of hypoglycemia with a serum blood glucose of 17 mg/dL (N >60 mg/dL). During the hospital admission, evaluation of hypoglycemia included a normal TSH of 1.170 (reference range [RR] 0.3-5.5 mIU/ml), fasting morning cortisol of 23.3 (RR >14-15 μg/dL), and a negative sulfonylurea screen. In addition, the patient had an undetectable level of Insulin <3.0 (RR 3-25 mU/L), Beta-hydroxybutyrate <0.10 (RR 0.02-0.27 mMol/L), C-peptide <0.1 (RR 0.5-3.3 ng/ml), and Pro-insulin <1.6 (RR 3-20 pmol/L). CT of the abdomen revealed disease progression with innumerable bilateral enhanced hypoattenuating masses in the liver. Management for refractory hypoglycemia required nutrition optimization, nausea control, close glucose monitoring, IV dextrose infusion, and intermittent intravenous glucagon for episodes of severe hypoglycemia (<40 mg/dL). During the hospitalization, the patient received the first cycle of chemotherapy with gemcitabine, cisplatin, and dexamethasone. On day 10 of admission, the IGF-2 resulted at 120 ng/ml (RR 180-580ng/ml) and IGF-1<10 (RR 50-317 ng/ml) with an IGF-2/IGF-1 ratio greater than 100 (cut off>10), diagnostic of a large nonislet cell tumor as the most likely cause of her severe hypoglycemia. Artificial nutrition did not align with this patient’s goals of care, so she was discharged from the hospital with a FreeStyle Libre 2 for continuous glucose monitoring. However, two weeks later, she returned to the emergency department with hypoglycemia (<40 mg/dL), ultimately choosing to pursue hospice. Conclusion: Patients with large liver tumor burden can experience hypoglycemia due to low glycogen content in the liver. In addition, these patients can have decreased oral intake and weight loss, which confounds the clinical scenario and can delay diagnostic workup. Patients with refractory hypoglycemia and nonislet cell tumors require further evaluation for IGF-2 production, and alternative temporary nutritional options should be discussed with the patient immediately. Therapeutic options depend on the ability to treat underlying cancer. Palliative chemotherapy, surgery, or radiation can be considered to control the tumor and improve hypoglycemia for quality of life when the cancer is otherwise untreatable. Presentation: Thursday, June 15, 2023