Hyperinsulinemic Hypoglycemia Associated with Metastatic Carcinosarcoma

Presentation Number: MON 290
Date of Presentation: April 3rd, 2017

Saba Wasim Aziz*
Johnson City Medical Center, Johnson City, TN

Abstract

Background:

Non islet cell tumor hypoglycemia (NICTH) is a well known but rare phenomenon caused primarily by tumors of mesenchymal or epithelial origin. The underlying mechanism of hypoglycemia in majority of these patients is overproduction of Insulin like Growth Factor 2 (IGF-2) by the tumor. However, rare cases of tumors of non-pancreatic origin secreting insulin have been reported. NICTH caused by carcinosarcoma is very rare. This is a novel case of hyperinsulinemic hypoglycemia associated with metastatic carcinosarcoma.

Clinical case:

A 66 year old Caucasian female was admitted for intractable nausea and vomiting for 2 weeks. She had been diagnosed with metastatic carcinosarcoma of unknown primary about one year ago, when she had presented with abdominal mass and pain and was currently undergoing chemotherapy with Doxorubicin. Patient had recurrent episodes of symptomatic hypoglycemia during her admission with blood glucose as low as 37 mg/dL, requiring repeated administration of intravenous dextrose. She continued to have episodes of hypoglycemia despite resolution of nausea and vomiting and adequate increase in oral intake. Liver function and renal function tests were unremarkable. 8am plasma cortisol was normal 17.3 mcg/dL. CT of the abdomen and pelvis showed very extensive intraperitoneal soft tissue mass involving most of the abdomen and pelvis with numerous prominent nodular masses in the mesentery but no abnormal lesions or metastasis was noted in the liver, pancreas or adrenal glands. Evaluation during an episode of hypoglycemia showed laboratory measured plasma glucose of 41 mg/dL. Simultaneously measured insulin level was 12.9 microU/mL (<3 microU/mL), C peptide level was 0.8 ng/mL (<0.6 ng/mL) and beta-hydroxybutyrate level was 0.12 mmol/L (>2.7 mmol/L) consistent with hyperinsulinemic hypoglycemia. Plasma glucose increased by 31 mg/dL 30min after administration of 1mg intravenous glucagon. Insulin antibody was undetectable and sulfonylurea and meglitinide panel was negative. IGF-I was low with low normal IGF-II (72 ng/mL 75-263 and 357 ng/mL 333-967, respectively). Patient was started on prednisone 60mg PO daily for recurrent hypoglycemia after which blood glucose stabilized. Given poor prognosis, she opted for hospice and was discharged home.

Conclusion:

NICTH is a rare paraneoplastic phenomenon and should be suspected as the cause of hypoglycemia in a patient with tumor. Clinicians should be aware of hyperinsulinemic hypoglycemia as a rare mechanism of hypoglycemia in these patients.

 

Nothing to Disclose: SWA