What is an insulinoma (insulin-producing tumor)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 10, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Surgical removal of the tumor is the primary treatment for insulinoma, and before surgery, patients should manage symptoms by stabilizing glucose levels with diet and/or diazoxide, as recommended by the panel 1. The management of insulinoma involves a combination of medical and surgical approaches.

  • Medical management includes stabilizing glucose levels with diet and/or diazoxide, as this can help control hypoglycemic symptoms.
  • Octreotide or lanreotide should be used with caution in patients with insulinoma, as they can suppress counterregulatory hormones and worsen hypoglycemia 1.
  • For acute hypoglycemic episodes, immediate treatment with oral glucose or intravenous dextrose is necessary. Some key points to consider in the management of insulinoma include:
  • The use of somatostatin analogues, such as octreotide or lanreotide, should be carefully considered, as they may not be effective in all patients and can have adverse effects 1.
  • The diagnosis of insulinoma is typically made through biochemical testing, including fasting hypoglycemia with inappropriately high insulin levels, and localization studies, such as CT, MRI, or endoscopic ultrasound 1.
  • Surgical removal of the tumor is the primary treatment for insulinoma, and laparoscopic or open surgical enucleation is performed for benign tumors, while malignant insulinomas may require partial pancreatectomy.
  • Most insulinomas (90%) are benign, and surgical removal is curative in most cases 1.

From the Research

Definition and Diagnosis of Insulinoma

  • Insulinoma is a rare tumor of the Langerhans islets of the pancreas that produces insulin and causes severe hypoglycemia with neuroglycopenic symptoms 2.
  • The diagnosis is based on the presence of Whipple's triad and the result of a fasting test 2, 3.
  • Insulinomas are most commonly benign, well-differentiated neuroendocrine tumors (NETs), whereas malignant neoplasms account for approximately 5-10% of all cases 4.

Treatment Options for Insulinoma

  • Surgery is the ideal treatment of insulinoma, and curative surgical excision remains the treatment of choice for single solitary insulinomas 5, 2, 3.
  • Systemic therapy may be required to prevent severe preoperative hypoglycemia, when surgery is contraindicated, delayed, or refused, and in case of unresectable metastatic disease 5.
  • Somatostatin analogues (octreotide and lanreotide) may be an alternative option for patients with insulinoma refractory and/or intolerant to diazoxide or with a high risk of fluid retention 5, 6.
  • Supportive measures and somatostatin receptor ligands can be used to control hypoglycemia 3.

Management of Insulinoma

  • Management includes conservative treatment with drugs targeting insulin-induced hypoglycemia, non-operative invasive procedures, as well as curative open or laparoscopic tumor resection 4.
  • For aggressive malignant cases, debulking procedures, somatostatin receptor ligands, peptide receptor radionuclide therapy, everolimus, sunitinib, and cytotoxic chemotherapy can be valuable options 3.
  • The centralization of patients is recommended due to the low incidence of the condition 2.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Approach to the Patient: Insulinoma.

The Journal of clinical endocrinology and metabolism, 2024

Research

Insulinomas: from diagnosis to treatment. A review of the literature.

Journal of B.U.ON. : official journal of the Balkan Union of Oncology, 2020

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.