SUN-284 Metastatic Insulinoma Refractory to Medical Management

Abstract Disclosure: M.R. Tejera: None. M. Essarani: None. M. Bassie: None. H. Amir: None. Insulinomas are rare pancreatic neuroendocrine tumors which lead to insulin hypersecretion causing symptoms of hypoglycemia. The majority of the insulinomas are often benign, but approximately 10% can be malignant. Due to metastatic insulinoma rarity there is insufficient data for clinical presentation and overall long term prognosis. We present a rare case of metastatic insulinoma with metastasis to the liver which was refractory to medical management and ultimately led to patient demise. A 63 year old female with history of insulinoma with metastasis to liver diagnosed in 2022 presented to the hospital for acute metabolic encephalopathy secondary to hypoglycemia. After her initial diagnosis, she was started on long acting octreotide 20 mg LAR monthly by her outpatient oncologist and referred to an endocrinologist. Despite octreotide therapy, she continued to have severe episodes of hypoglycemia requiring diazoxide 3 mg/kg/day. Both octreotide and diazoxide doses were increased outpatient to 30 mg LAR monthly and 100 mg every 8 hours respectively. Unfortunately, the patient was lost to follow up for 2 years and presented to the hospital with acute metabolic encephalopathy found to be severely hypoglycemic. She was initially started on D5W, diazoxide, and octreotide as her previous hospital records were within the hospital electronic medical record system making her metastatic insulinoma history known. With continued hypoglycemia, fluids were increased to D20 and diazoxide was up titrated to max 8 mg/kg/day. Despite these interventions, she had persistent hypoglycemia. Attempts to transfer to a tertiary care facility were made but hindered by alternative factors. She was ultimately intubated due to respiratory distress from severe edema sequentially due to high diazoxide doses and persistent fluids despite diuretics. CRRT was initiated due to severe electrolyte abnormality and volume overload. Due to being medically unstable, patient was deemed a poor candidate for tumor debulking surgery as well as being unable to receive liver directed therapy. She was transitioned to comfort care by family members and the patient ultimately expired. The primary treatment of choice for metastatic insulinomas is surgical resection of the primary tumor. While patients may still experience hypoglycemic episodes after surgery, medical management with diazoxide and octreotide are often used. Patients with metastatic disease despite surgery will often have prolonged survival due to the slow growing nature of the tumors. The 2 year loss to follow up with inconsistent medical management allowed for missed opportunities for liver directed therapy or surgical intervention. With the combination of TPN, IV fluids, and elevated diazoxide and octreotide doses, the patient developed respiratory distress and was intubated. Volume overload is a common side effect of diazoxide and must be closely monitored. Presentation: Sunday, July 13, 2025