S5619 Refractory Hypoglycemia in a Young Woman With a Large Hepatic Mass: A Case of Non-Islet Cell Tumor Hypoglycemia

Introduction: Non-islet cell tumor hypoglycemia (NICTH) is a paraneoplastic syndrome characterized by hypoglycemia from excessive production of insulin-like growth factor-2 (IGF-2) by tumors. We present a case of a 31-year-old woman who was found to be severely and persistently hypoglycemic secondary to a liver mass. Case Description/Methods: A 31-year-old woman with a history of endometrial stromal sarcoma status post total hysterectomy with bilateral salpingectomy 5 years ago, followed by chemotherapy, presented with a week-long history of lethargy, dizziness, and recurrent falls. Her blood glucose ranged between 26-28 mg/dl. Despite receiving multiple doses of intravenous dextrose in the emergency room, she was persistently hypoglycemic, which necessitated a transfer to the ICU for management of refractory hypoglycemia. She was started on a dextrose drip, and workup revealed low insulin and C-peptide levels (0.4 mc Intl units/ml and 0.1 ng/ml), beta-hydroxybutyrate of 0.7 mg/dl, normal IGF-2 level of 515 ng/ml. ACTH stimulation test was normal, and sulphonylurea levels were negative. The patient remained hypoglycemic despite continuous replacement. MRI abdomen/pelvis revealed a 15 cm right hepatic mass, raising a concern for a tumoral production of an insulin-like factor or a glucose-consumptive tumor with reduced hepatic gluconeogenesis contributing to her presentation. A right hepatic lobe resection was done with a dramatic increase in blood glucose level to normal limits. Pathology examination showed high-grade sarcoma positive for CD56, CyclinD1, CD99, and BCOR, consistent with metastatic high-grade endometrial stromal sarcoma. Discussion: NICTH diagnosis can be confirmed by an elevated IGF2 level or IGF-2/IGF-1 ratio. However, in critically ill patients in the setting of an underlying tumor, the mechanism of hypoglycemia could be explained by the extensive tumor burden in the liver. The presence of hypoinsulinemic hypoglycemia with low C-peptide levels can support this conclusion. Although the IGF2 level was normal and IGF-2/IGF-1 ratio was not documented, the improvement in her clinical status and biochemical profile with tumor resection and after exclusion of other causes of hypoglycemia support the diagnosis of NICTH. This case highlights a unique presentation of recurrent high-grade endometrial stromal sarcoma and emphasizes the importance of post-treatment cancer surveillance.