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Robotic Enucleation of an Intra-Pancreatic Insulinoma in the Pancreatic Head
Published on: January 3, 2020
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Metastatic Insulinoma Presenting With Postprandial Hypoglycemia
Monique Debrah Maher1, Dimpi Nitin Desai2, Mandeep Bajaj2
1Department of Internal Medicine/Pediatrics, Baylor College of Medicine, Houston, Texas.
AACE Clinical Case Reports
|August 12, 2022
Summary
Pancreatic neuroendocrine tumors can cause postprandial hypoglycemia without fasting symptoms. Measuring proinsulin levels is crucial for diagnosing insulinoma, especially when reactive hypoglycemia treatments fail.
Area of Science:
- Endocrinology
- Oncology
- Gastroenterology
Background:
- Insulinoma, a pancreatic neuroendocrine tumor, typically causes fasting hypoglycemia.
- Rarely, insulinoma can exclusively present with postprandial hypoglycemia.
Observation:
- A 69-year-old man experienced recurrent postprandial hypoglycemia with symptoms like blurred vision, sweating, and confusion.
- Continuous glucose monitoring confirmed hypoglycemia exclusively within 2 hours after meals.
- Elevated proinsulin levels were detected during a monitored fast with hypoglycemia.
Findings:
- A pancreatic lesion was identified via CT scan and confirmed as a low-grade, well-differentiated neuroendocrine tumor with lymphovascular invasion.
- The patient's presentation and diagnostic workup confirmed insulinoma as the cause of exclusive postprandial hypoglycemia.
Implications:
- This case underscores the importance of considering insulinoma in patients with persistent postprandial hypoglycemia, even without fasting hypoglycemia.
- Measuring proinsulin levels is essential for diagnosing insulinoma when initial management for reactive hypoglycemia is ineffective.
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