{
  "schemaVersion": 2,
  "eyebrow": "Endocrinology",
  "title": "Insulinoma",
  "summary": "Confirm endogenous hyperinsulinemic hypoglycemia before imaging, then localize and stage for parenchyma-sparing cure when feasible. Persistent or metastatic disease requires continuous hypoglycemia prevention and multidisciplinary tumor-directed therapy selected by resectability and receptor imaging.",
  "seoDescription": "Physician guide to biochemical confirmation, localization, surgical management, and treatment of persistent or metastatic insulinoma.",
  "clinicalQuestion": "How should physicians confirm, localize, and treat insulinoma while preventing recurrent hypoglycemia?",
  "specialty": "Endocrinology",
  "audience": "U.S. physicians and medical trainees",
  "tags": [
    "insulinoma",
    "endogenous hyperinsulinemic hypoglycemia",
    "72-hour fast",
    "GLP-1 receptor PET",
    "pancreatic neuroendocrine tumor",
    "MEN1"
  ],
  "keyTakeaways": [
    "Obtain a critical sample during documented hypoglycemia before localization: glucose, insulin, C-peptide, proinsulin, beta-hydroxybutyrate, and sulfonylurea/meglitinide testing distinguish endogenous hyperinsulinism from exogenous insulin or secretagogue exposure. [16]",
    "A supervised fast is indicated when a spontaneous critical sample is unavailable; glucose below 55 mg/dL with insulin at least 3 µU/mL, C-peptide at least 0.6 ng/mL, proinsulin at least 5 pmol/L, beta-hydroxybutyrate no more than 2.7 mmol/L, and a negative secretagogue screen supports endogenous hyperinsulinemic hypoglycemia. [14][21]",
    "After biochemical confirmation, use pancreas-protocol CT for initial localization and metastatic assessment; add EUS or MRI for localized disease and GLP-1 receptor PET when conventional studies are unrevealing. [13][22]",
    "Solitary localized insulinoma is generally managed with curative surgical excision; operative strategy depends on anatomic localization and whether enucleation can preserve pancreatic parenchyma. [13][20][22]",
    "Do not assume somatostatin receptor imaging will exclude insulinoma: more than 50% may be missed by somatostatin receptor scintigraphy because receptor density is often low. [9]",
    "Metastatic or unresectable disease requires both glucose-directed therapy and tumor control; somatostatin receptor ligand therapy, everolimus, and peptide receptor radionuclide therapy are options selected by tumor biology and receptor expression. [3][8][22]"
  ],
  "sections": [
    {
      "id": "confirm-endogenous-hyperinsulinism",
      "eyebrow": "Diagnostic priority",
      "heading": "Confirm the biochemical diagnosis before pancreatic imaging",
      "intro": "A pancreatic lesion is not diagnostic without a contemporaneous hypoglycemic critical sample.",
      "paragraphs": [
        "Evaluate patients with Whipple triad or recurrent fasting neuroglycopenia by drawing plasma glucose, insulin, C-peptide, proinsulin, beta-hydroxybutyrate, and a sulfonylurea/meglitinide screen during spontaneous hypoglycemia. Give glucagon 1 mg IV after the specimen is collected; a plasma glucose rise greater than 25 mg/dL supports hyperinsulinemic hypoglycemia. [16]",
        "At plasma glucose below 55 mg/dL, insulin of at least 3 µU/mL, C-peptide of at least 0.6 ng/mL, proinsulin of at least 5 pmol/L, beta-hydroxybutyrate no more than 2.7 mmol/L, and a negative sulfonylurea screen support endogenous hyperinsulinemic hypoglycemia. These results establish the physiologic syndrome requiring localization; they do not by themselves prove a pancreatic insulinoma. [14][21]",
        "A low C-peptide in the setting of detectable insulin redirects the evaluation toward exogenous insulin exposure. Detectable sulfonylurea or meglitinide redirects management toward secretagogue-associated hypoglycemia rather than tumor localization. Suppressed ketogenesis, reflected by beta-hydroxybutyrate below 2.7 mmol/L, is a key discriminator of insulin-mediated hypoglycemia. [15][16]"
      ],
      "bullets": [],
      "subsections": [],
      "table": {
        "caption": "Critical-sample interpretation for suspected insulin-mediated hypoglycemia. [14][16][21]",
        "columns": [
          "Finding during hypoglycemia",
          "Interpretation",
          "Immediate next step"
        ],
        "rows": [
          [
            "Glucose <55 mg/dL, insulin ≥3 µU/mL, C-peptide ≥0.6 ng/mL, proinsulin ≥5 pmol/L, beta-hydroxybutyrate ≤2.7 mmol/L, negative secretagogue screen [14][21]",
            "Endogenous hyperinsulinemic hypoglycemia [14][21]",
            "Proceed to pancreatic localization and staging. [13][22]"
          ],
          [
            "Insulin present with low C-peptide [16]",
            "Exogenous insulin effect is favored. [16]",
            "Investigate insulin exposure; do not attribute the episode to insulinoma without further evidence. [16]"
          ],
          [
            "Sulfonylurea or meglitinide detected [16]",
            "Insulin secretagogue-associated hypoglycemia [16]",
            "Address medication or covert exposure; pancreatic localization is not the initial next step. [16]"
          ],
          [
            "Beta-hydroxybutyrate ≥2.7 mmol/L [15][16]",
            "Insulin-mediated suppression of ketogenesis is not supported. [15][16]",
            "Reassess non-insulin-mediated causes of hypoglycemia. [15]"
          ]
        ]
      }
    },
    {
      "id": "supervised-fast",
      "eyebrow": "Provocative testing",
      "heading": "Use a supervised fast when no spontaneous critical sample is available",
      "intro": "The 72-hour fast remains the reference test for suspected fasting insulinoma.",
      "paragraphs": [
        "Perform a monitored fast when the clinical history is compelling but an episode has not been captured. Permit noncaloric, caffeine-free beverages; measure glucose, insulin, and C-peptide at baseline and every 4 to 6 hours. Once plasma glucose falls below 60 mg/dL, increase sampling to every 1 to 2 hours with close observation. [16]",
        "Terminate the fast when neuroglycopenic symptoms occur with plasma glucose below 45 mg/dL; the Endocrine Society threshold cited in Endotext is below 55 mg/dL. At termination, obtain glucose, insulin, C-peptide, proinsulin, beta-hydroxybutyrate, and an oral insulin secretagogue screen before treating hypoglycemia. [16]",
        "Most patients with insulinoma develop symptomatic hypoglycemia before the full 72 hours: approximately one-third by 12 hours, 80% by 24 hours, and 90% by 48 hours. A negative or non-diagnostic fast should prompt reconsideration of the event phenotype, particularly postprandial rather than fasting hypoglycemia, before pursuing invasive localization. [21]"
      ],
      "bullets": [
        "Do not order CT, MRI, EUS, or receptor PET as the first diagnostic step when endogenous hyperinsulinism has not been demonstrated; incidental pancreatic lesions can misdirect management. [13][14]",
        "Continue usual waking activity during the fast when safe, because activity may facilitate diagnostic hypoglycemia. [16]"
      ],
      "subsections": [],
      "table": {
        "caption": "",
        "columns": [],
        "rows": []
      }
    },
    {
      "id": "localize-and-stage",
      "eyebrow": "Imaging sequence",
      "heading": "Localize only after biochemical confirmation and stage before surgery",
      "intro": "Imaging determines resectability and the safest parenchyma-preserving operation.",
      "paragraphs": [
        "Begin with contrast-enhanced CT to localize the pancreatic lesion and determine whether metastatic disease is present. For an apparently indolent localized lesion, use EUS or MRI as the next anatomic study when CT is negative or insufficient for procedural planning. Approximately 30% of insulinomas are smaller than 1 cm, making localization technically challenging. [13][22]",
        "When CT, MRI, and EUS do not identify a lesion in biochemically proven endogenous hyperinsulinism, obtain GLP-1 receptor PET/CT or PET/MRI for occult, localized insulinoma. This modality is described as highly sensitive for indolent localized lesions and can avoid blind pancreatic resection. [13][22]",
        "Somatostatin receptor imaging has a different role. Gallium-68 somatostatin analogue PET/CT is the most sensitive modality for pNET and NET localization broadly and is recommended for surgical candidates and advanced disease staging, but conventional somatostatin receptor scintigraphy frequently misses insulinomas because of lower receptor density. A negative somatostatin receptor study therefore should not end the localization workup for a suspected small localized insulinoma. [9][12]",
        "If noninvasive studies remain negative despite unequivocal endogenous hyperinsulinemic hypoglycemia, refer to a high-volume pancreatic NET center for specialized localization and operative planning. Intraoperative palpation and intraoperative ultrasonography are important adjuncts, particularly when preoperative imaging is incomplete. [4][20]"
      ],
      "bullets": [],
      "subsections": [
        {
          "heading": "When to assess for MEN1",
          "paragraphs": [
            "Consider MEN1 in patients with multiple pancreatic lesions, recurrent or metachronous insulinomas, or personal evidence of primary hyperparathyroidism or pituitary tumor. Approximately 4% of patients with insulinoma have MEN1, and multiple lesions are particularly associated with MEN1. [10][13]"
          ],
          "bullets": []
        }
      ],
      "table": {
        "caption": "Localization strategy after biochemical confirmation of endogenous hyperinsulinemic hypoglycemia. [9][12][13][22]",
        "columns": [
          "Clinical setting",
          "Preferred next study",
          "Decision consequence"
        ],
        "rows": [
          [
            "Initial localization and metastatic assessment",
            "Contrast-enhanced CT [13][22]",
            "Defines visible pancreatic lesion, liver or other metastatic disease, and operative pathway. [13][22]"
          ],
          [
            "CT-negative or incompletely characterized presumed localized disease",
            "EUS or MRI [13][22]",
            "Improves localization for enucleation versus pancreatic resection planning. [13]"
          ],
          [
            "Biochemically proven disease occult on conventional imaging",
            "GLP-1 receptor PET/CT or PET/MRI [13][22]",
            "Targets occult indolent localized insulinoma for definitive surgery. [13][22]"
          ],
          [
            "Advanced disease or surgical staging of NET extent",
            "Gallium-68 somatostatin analogue PET/CT [12]",
            "Defines somatostatin receptor expression and whole-body disease burden; a negative result does not exclude insulinoma. [9][12]"
          ]
        ]
      }
    },
    {
      "id": "prevent-hypoglycemia",
      "eyebrow": "Bridge to definitive care",
      "heading": "Prevent recurrent hypoglycemia while localization and definitive therapy proceed",
      "intro": "Recurrent neuroglycopenia requires active glucose prevention, not outpatient observation alone.",
      "paragraphs": [
        "Patients with frequent fasting hypoglycemia, impaired awareness, seizures, or altered consciousness need immediate carbohydrate rescue and monitored glucose support while the critical sample and localization pathway are completed. During operative care, use perioperative glucose monitoring to detect and prevent hypoglycemia. [2][24]",
        "For persistent hypoglycemia when surgery is delayed, contraindicated, or noncurative, use dietary measures and medical therapy to reduce hypoglycemia burden. Somatostatin receptor ligands may be used for hypoglycemia control, but therapeutic selection should account for receptor imaging and clinical response rather than presuming uniform benefit. [22][3]",
        "Continuous glucose monitoring can provide practical surveillance in patients with recurrent or poorly perceived hypoglycemia, particularly during medical bridging or advanced disease management; it complements but does not replace laboratory confirmation of endogenous hyperinsulinism. [3]"
      ],
      "bullets": [
        "Escalate to inpatient management when recurrent neuroglycopenia cannot be reliably prevented with oral intake or when intravenous glucose is repeatedly required. [2][24]",
        "Avoid delaying definitive tumor assessment solely because interim glucose-directed measures reduce symptoms; durable cure for a resectable localized insulinoma is surgical. [13][22]"
      ],
      "subsections": [],
      "table": {
        "caption": "",
        "columns": [],
        "rows": []
      }
    },
    {
      "id": "definitive-localized-treatment",
      "eyebrow": "Curative treatment",
      "heading": "Resect localized insulinoma with a pancreas-preserving strategy when feasible",
      "intro": "The operative objective is cure of hypoglycemia while minimizing loss of pancreatic tissue.",
      "paragraphs": [
        "Offer surgery for a solitary localized insulinoma after biochemical confirmation and conclusive localization. Surgical excision is the treatment of choice and is generally curative for localized pancreatic insulinoma. Select enucleation when lesion location permits safe parenchymal preservation; use partial pancreatectomy when anatomy precludes enucleation or requires formal resection. [13][20][22]",
        "Use preoperative lesion location to choose minimally invasive, robot-assisted, or open surgery and to plan enucleation versus partial pancreatectomy. Intraoperative ultrasound and palpation can confirm lesion position and relationship to the pancreatic duct, particularly for small or occult tumors. [13][20]",
        "Counsel patients about pancreatic morbidity when selecting the operative approach. In one three-decade surgical series, pancreatic fistula occurred in 44%, severe complications in 30%, overall morbidity in 72%, and mortality in 6%; these outcomes reflect a reported surgical cohort and reinforce the importance of experienced multidisciplinary pancreatic surgery. [5]",
        "Pathology should document neuroendocrine differentiation with chromogranin A and synaptophysin immunostaining plus insulin staining; determine mitotic index and Ki-67 for grading and apply current WHO TNM classification. [9][14]"
      ],
      "bullets": [],
      "subsections": [
        {
          "heading": "Postoperative surveillance",
          "paragraphs": [
            "After R0 resection of a benign sporadic solitary G1-G2 insulinoma, obtain a follow-up assessment at 3 to 6 months; recurrent imaging is not routinely proposed unless symptoms recur. Measure chromogranin A only if it was elevated initially. [20]"
          ],
          "bullets": [
            "Recurrent fasting hypoglycemia after surgery warrants repeat biochemical confirmation and renewed localization rather than assuming postoperative recurrence from symptoms alone. [16][20]"
          ]
        }
      ],
      "table": {
        "caption": "",
        "columns": [],
        "rows": []
      }
    },
    {
      "id": "advanced-or-unresectable-disease",
      "eyebrow": "Disease control",
      "heading": "Treat unresectable or metastatic insulinoma with parallel glucose and tumor control",
      "intro": "Metastases establish malignant behavior and shift management from cure by local excision to multidisciplinary disease control.",
      "paragraphs": [
        "Assess resectability and metastatic burden with cross-sectional and receptor-based imaging before selecting therapy. For aggressive malignant disease, management may combine debulking procedures, somatostatin receptor ligand therapy, everolimus, and peptide receptor radionuclide therapy; selection depends on disease extent, clinical hypoglycemia, and somatostatin receptor expression. [22]",
        "Consider peptide receptor radionuclide therapy in metastatic or inoperable disease, particularly when somatostatin receptor expression is demonstrated. A contemporary review describes PRRT as a first-line approach alongside somatostatin analogues for metastatic or inoperable insulinoma because it can improve progression-free survival and provide durable improvement in hypoglycemia; the strength of evidence is limited by the rarity of the disease. [3]",
        "Everolimus has produced rapid glycemic responses in metastatic insulinoma, including plasma glucose normalization within 14 days in a small report, and should be considered in refractory hypoglycemia when tumor-directed systemic therapy is needed. Sirolimus improved glycemic control in four infants with diffuse hyperinsulinemic hypoglycemia unresponsive to diazoxide and octreotide, but that pediatric experience should not be extrapolated as standard adult insulinoma therapy. [1]",
        "For liver-dominant metastatic disease with refractory hypoglycemia, liver-directed therapy may be considered within a NET multidisciplinary program. A reported case of unresectable malignant insulinoma with liver metastases had hypoglycemia resolution after four courses of lutetium-177 dotatate PRRT, following incomplete response to long-acting octreotide and everolimus. [8]"
      ],
      "bullets": [
        "Obtain somatostatin receptor imaging before considering receptor-targeted PRRT; higher somatostatin receptor expression supports this strategy. [8][12]",
        "Continue close glucose monitoring during systemic or radionuclide therapy because symptomatic benefit and antitumor response may not occur synchronously. [3][8]"
      ],
      "subsections": [],
      "table": {
        "caption": "Treatment direction for noncurable insulinoma. [3][8][22]",
        "columns": [
          "Clinical branch",
          "Management direction",
          "Selection discriminator"
        ],
        "rows": [
          [
            "Resectable localized disease",
            "Curative surgical excision, favoring parenchyma preservation when technically feasible. [13][20][22]",
            "Solitary localized lesion with operative candidacy. [13][22]"
          ],
          [
            "Unresectable or metastatic disease with hypoglycemia",
            "Dietary and glucose-directed support plus somatostatin receptor ligand therapy and tumor-directed treatment. [3][22]",
            "Symptom burden, tumor extent, and treatment response. [3][22]"
          ],
          [
            "Somatostatin receptor-positive metastatic or inoperable disease",
            "Consider PRRT with lutetium-177 dotatate in a NET multidisciplinary program. [3][8]",
            "Demonstrated receptor expression on somatostatin receptor imaging. [8][12]"
          ],
          [
            "Refractory metastatic hypoglycemia requiring systemic control",
            "Consider everolimus as tumor- and glucose-directed therapy. [1][22]",
            "Persistent hypoglycemia despite initial measures and need for systemic disease control. [1][22]"
          ]
        ]
      }
    }
  ],
  "faq": [
    {
      "question": "Does a negative somatostatin receptor scan exclude insulinoma?",
      "answer": "No. Insulinomas often have low somatostatin receptor density, and more than 50% may be missed by somatostatin receptor scintigraphy. In biochemically proven disease with unrevealing CT, MRI, and EUS, proceed to GLP-1 receptor PET/CT or PET/MRI for occult localized lesions. [9][13][22]"
    }
  ],
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  "editorialNote": "Prepared from cited clinical literature using Astra's research workflow. Verify recommendations against current guidance and patient-specific factors.",
  "citations": [
    {
      "number": 1,
      "title": "Sirolimus Therapy in Infants with Severe Hyperinsulinemic Hypoglycemia | New England Journal of Medicine",
      "detail": "www.nejm.org",
      "url": "https://www.nejm.org/doi/full/10.1056/NEJMoa1310967",
      "authors": "www.nejm.org",
      "host": "www.nejm.org",
      "snippet": "A possible mechanism of hyperinsulinism and beta-cell hyperplasia in diffuse hyperinsulinemic hypoglycemia involves the constitutive activation of the mTOR pathway.5 The serine–threonine protein kinase mTOR has been implicated in the cellular response to nutrients and growth factor signaling.6 The m",
      "score": 0.44724357
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    {
      "number": 2,
      "title": "Insulin Blood Level - an overview | ScienceDirect Topics",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/topics/immunology-and-microbiology/insulin-blood-level",
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      "host": "www.sciencedirect.com",
      "snippet": "This patient has a prolactinoma, manifested by impotence, headaches, bitemporal hemianopsia, and a significantly elevated serum prolactin level. Hypercalcemia with an elevated serum PTH level indicates that he also has hyperparathyroidism. The MEN type 1 (MEN-1) syndrome, which consists of hyperpara",
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    {
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      "title": "Managing Hypoglycaemia in Patients With Insulinoma—A Tertiary Centre Experience and Review of the Literature - Howarth - 2025 - Clinical Endocrinology - Wiley Online Library",
      "detail": "onlinelibrary.wiley.com",
      "url": "https://onlinelibrary.wiley.com/doi/full/10.1111/cen.15188",
      "authors": "onlinelibrary.wiley.com",
      "host": "onlinelibrary.wiley.com",
      "snippet": "PRRT is an effective treatment offering improvement in progression free survival and long-term improvement in hypoglycaemia and should be considered as a first line treatment approach in addition to somatostatin analogues in patients with metastatic or inoperable disease. Huhtala, et al., “Character",
      "score": 0.5040288
    },
    {
      "number": 4,
      "title": "The surgical management of insulinomas in children - ScienceDirect",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/abs/pii/S0022346813003989",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "### J Pediatr Surg\n\n### Nuclear medicine in the detection and management of pancreatic islet-cell tumours\n\n### Best Pract Res Clin Endocrinol Metab\n\n### Blind distal pancreatectomy for occult insulinoma, an inadvisable procedure\n\n### J Am Coll Surg\n\n### Pancreatic head resection and roux-en-Y pancre",
      "score": 0.45231876
    },
    {
      "number": 5,
      "title": "Surgical management of insulinoma over three decades",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/pii/S1365182X21001131",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "by A de Carbonnières · 2021 · Cited by 42 — The mortality rate was 6% (n = 5), with a morbidity rate of 72%, including 24 severe complications (30%) and 35 pancreatic fistulas (44%).",
      "score": 0.42763633
    },
    {
      "number": 6,
      "title": "Effect of octreotide on plasma concentrations of glucose, insulin, glucagon, growth hormone, and cortisol in healthy dogs and dogs with insulinoma - ScienceDirect",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/abs/pii/S0034528805000597",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "### Israel Journal of Medical Sciences\n\n### Diazoxide in the management of patients with insulinoma\n\n### World Journal of Surgery\n\n### Positive somatostatin receptor scintigraphy correlates with the presence of somatostatin subtype 2\n\n### Gut\n\n### Effects of somatostatin and SMS 201-995 on carbohydr",
      "score": 0.41478088
    },
    {
      "number": 7,
      "title": "Enucleation of insulinoma using laparoscopic distal ...",
      "detail": "academic.oup.com",
      "url": "https://academic.oup.com/jscr/article/2024/8/rjae561/7746094",
      "authors": "academic.oup.com",
      "host": "academic.oup.com",
      "snippet": "by LF Marcial-Cuevas · 2024 — In this case report, we present surgical treatment for insulinoma, highlighting the diagnostic challenges and therapeutic strategies employed.Read more",
      "score": 0.39522812
    },
    {
      "number": 8,
      "title": "Advanced Peptide Receptor Radionuclide Therapy to... : Journal of Medical Sciences",
      "detail": "journals.lww.com",
      "url": "https://journals.lww.com/joms/fulltext/2025/09000/advanced_peptide_receptor_radionuclide_therapy_to.7.aspx",
      "authors": "journals.lww.com",
      "host": "journals.lww.com",
      "snippet": "## CONCLUSION\n\nIn summary, this case report presents a rare instance of refractory malignant insulinoma with multiple liver metastases, which remained unresponsive to initial treatment, failing to improve hypoglycemia or reduce tumor size. Consequently, the patient experienced substantial improvemen",
      "score": 0.81630427
    },
    {
      "number": 9,
      "title": "ENETS Consensus Guidelines for the Management of Patients with Digestive Neuroendocrine Neoplasms: Functional Pancreatic Endocrine Tumor Syndromes",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC3701449",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "#### Minimal Consensus Statements for Diagnosis of Insulinomas - Specific [1][2][3][13][14][15][50][66][67][89][90]\n\nClassically, clinical symptoms are required for the diagnosis of insulinoma and the diagnosis of insulinoma is absolutely established using the following six criteria: (1) documented blood gluc",
      "score": 0.7458619
    },
    {
      "number": 10,
      "title": "NANETS Treatment Guidelines: Well-Differentiated Neuroendocrine ...",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC3100728",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "Insulinomas have an estimated annual incidence of 1 to 4 per million persons. Approximately 4% of patients with insulinoma have MEN I.67 Insulinomas are usually single tumors (except in patients with MEN I), generally small (ie, <1 cm), and almost always (>99%) intrapancreatic in location and, in co",
      "score": 0.6829338
    },
    {
      "number": 11,
      "title": "Multicenter Study on the Clinical Characteristics, Diagnosis, and Treatment Outcomes of Insulinoma: Insights From 15 Medical Centres",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12134450",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "34. M. Falconi ,  B. Eriksson ,  G. Kaltsas , et al., “ENETS Consensus Guidelines Update for the Management of Patients with Functional Pancreatic Neuroendocrine Tumors and Non‐Functional Pancreatic Neuroendocrine Tumors,” _Neuroendocrinology_ 103, no. 2 (2016): 153–171. doi: 10.1159/000443171  [DOI",
      "score": 0.66308063
    },
    {
      "number": 12,
      "title": "Consensus guidelines update for the management of functional p-NETs (F-p-NETs) and non-functional p-NETs (NF-p-NETs)",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC4849884",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "165.Mehrabi A, Fischer L, Hafezi M, _et al_. A systematic review of localization, surgical treatment options, and outcome of insulinoma. _Pancreas_. 2014. 43:675-686. doi: 10.1097/MPA.0000000000000110 [DOI] [PubMed] [Google Scholar]\n   166.Guo Q, Wu Y. Surgical treatment of pancreatic islet cell tum",
      "score": 0.657561
    },
    {
      "number": 13,
      "title": "Insulinoma - Endotext - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK278981",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "Once the diagnosis of insulinoma is confirmed, every effort should be made to localize the tumor. Preoperative localization is important because approximately 30% of insulinomas are less than 1 cm in diameter and 10% are multiple, the latter particularly is present in MEN-1 patients (16). In additio",
      "score": 0.57408494
    },
    {
      "number": 14,
      "title": "Insulinoma - StatPearls - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK544299",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "As with all functional endocrine tumors, a biochemical diagnosis should be made before localization studies are performed.(#article-23569.r1) Evaluation begins with the demonstration of hypoglycemia and inappropriate hyperinsulinemia. Diagnostic criteria include a plasma glucose concentration of les",
      "score": 0.5104727
    },
    {
      "number": 15,
      "title": "Non-Diabetic Hypoglycemia - StatPearls - NCBI Bookshelf",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK573079",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "Fasting Hypoglycemia\n\nInsulinoma, neoplasia, alcohol, and drugs are examples of conditions that lead to fasting hypoglycemia. A 72 hour fast is the gold standard test for the biochemical confirmation of insulinoma. Elevated insulin and C-peptide levels, in the setting of hypoglycemia, with a negativ",
      "score": 0.7318455
    },
    {
      "number": 16,
      "title": "Hypoglycemia - Endotext - NCBI Bookshelf - NIH",
      "detail": "www.ncbi.nlm.nih.gov",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK279137",
      "authors": "www.ncbi.nlm.nih.gov",
      "host": "www.ncbi.nlm.nih.gov",
      "snippet": "To confirm the diagnosis and explore etiology, it is necessary to collect blood samples during hypoglycemia, whether it occurs spontaneously or by provoked testing that can be selected based on clues from the medical history. One should measure plasma glucose, insulin, c-peptide, proinsulin, and bet",
      "score": 0.6077801
    },
    {
      "number": 17,
      "title": "Clinical characteristics and treatment outcomes of patients ...",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/pii/S2405844025001793",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "by W Li · 2025 · Cited by 3 — The incidence of pancreatic fistula, bleeding and major complications after the operation of pancreatic head/neck insulinoma was higher than ...Read more",
      "score": 0.33228928
    },
    {
      "number": 18,
      "title": "Octreotide - an overview | ScienceDirect Topics",
      "detail": "sciencedirect.com",
      "url": "https://sciencedirect.com/topics/agricultural-and-biological-sciences/octreotide",
      "authors": "sciencedirect.com",
      "host": "sciencedirect.com",
      "snippet": "| Octreotide | Octreotide is a long-acting somatostatin octapeptide analog that inhibits pancreatic secretion directly and indirectly by suppressing secretion of cholecystokinin and secretin from the small intestine (Nemeth, 2002). Early clinical studies with this agent produced conflicting results ",
      "score": 0.3239578
    },
    {
      "number": 19,
      "title": "Management of Intractable Hypoglycemia With Yttirum-90 Radioembolization in a Patient With Malignant Insulinoma - ScienceDirect",
      "detail": "www.sciencedirect.com",
      "url": "https://www.sciencedirect.com/science/article/abs/pii/S0002962915314592",
      "authors": "www.sciencedirect.com",
      "host": "www.sciencedirect.com",
      "snippet": "### N Engl J Med\n\n### Failure to confirm major objective antitumor activity for streptozocin and doxorubicin in the treatment of patients with advanced islet cell carcinoma\n\n### Cancer\n\n### Doxorubicin, streptozocin, and 5-fluorouracil chemotherapy for patients with metastatic islet-cell carcinoma\n\n",
      "score": 0.25480598
    },
    {
      "number": 20,
      "title": "Changes in diagnosis and operative treatment of insulinoma over two decades - PMC",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC10310606",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "to the early 2000s, surgical excision of the insulinoma after bidigital exploration of the pancreas and intraoperative ultrasound (IOUS) without further preoperative investigations was the procedure of choice, when a diffuse metastatic disease was excluded . In the last decade, however, imaging moda",
      "score": 0.6307082
    },
    {
      "number": 21,
      "title": "Insulinoma—Accurate Preoperative Localization Is the Key to Management: An Initial Experience",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC9240150",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "between the onset of the symptoms and the diagnosis. Insulinoma is confirmed by the presence of endogenous hyperinsulinemic hypoglycemia. The diagnostic “gold standard” for insulinoma is the 72-h fast test . One-third of patients develop corresponding symptoms within 12 h, 80% within 24 h, 90% withi",
      "score": 0.62495816
    },
    {
      "number": 22,
      "title": "Approach to the Patient: Insulinoma - PMC",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC10940262",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "of insulinomas are associated with the multiple endocrine neoplasia type 1 syndrome. Localization of the insulinoma and exclusion or confirmation of metastatic disease by computed tomography is followed by endoscopic ultrasound or magnetic resonance imaging for indolent, localized insulinomas. Gluca",
      "score": 0.6175132
    },
    {
      "number": 23,
      "title": "Diagnostic Modalities, Management Considerations, and Outcomes of Insulinoma: A Case Series from a Tertiary Care Centre - PMC",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC11288522",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "In the evaluation of insulinoma, there are two crucial steps: the first is to establish the diagnosis, and the second one is to localize the tumour. Establishing the diagnosis requires fulfilment of the classical Whipple’s triad, which includes documented hypoglycaemia (plasma glucose <55 mg/dl), sy",
      "score": 0.59372765
    },
    {
      "number": 24,
      "title": "ENETS Consensus Guidelines for the Standards of Care in Neuroendocrine Tumors: Pre- and Perioperative Therapy in Patients with Neuroendocrine Tumors",
      "detail": "pmc.ncbi.nlm.nih.gov",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC5637287",
      "authors": "pmc.ncbi.nlm.nih.gov",
      "host": "pmc.ncbi.nlm.nih.gov",
      "snippet": "### Insulinoma [...] ##  is needed for patients with gastrinoma mainly to prevent gastrojejunal bleeding, and perioperative glucose monitoring is used to avoid hypoglycemia in patients with insulinoma. Patients with glucagonoma require somatostatin analog treatment and nutritional supplementation to",
      "score": 0.5735118
    }
  ],
  "publishedAt": "2026-09-16T00:25:58.812297+00:00",
  "updatedAt": "2026-09-16T00:25:58.812297+00:00",
  "readingMinutes": 6,
  "slug": "insulinoma"
}