{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T05:05:50Z","timestamp":1789967150274,"version":"4.0.1"},"reference-count":45,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Endocrinol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Insulinoma is a rare endocrine tumor that is clinically characterized by the Whipple\u2019s triad and can be part of multiple endocrine neoplasia syndrome type 1 (MEN1). Most insulinomas are less than 2\u00a0cm, but the smaller the tumor diameter, the lower the imaging sensitivity. Here we present a case of recurrent asymptomatic hypoglycemia with unremarkable contrast-enhanced CT and MRI imaging that led to the delayed identification of an insulinoma. The tumor was localized with the invasive selective arterial calcium stimulation test (SACST).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Case presentation<\/jats:title>\n                    <jats:p>A 59-year-old female presented with asymptomatic hypoglycemia detected in preoperative screening on two occasions over the past year. She had no classic symptoms of hypoglycemia such as dizziness, weakness, blackouts, anxiety, palpitations, tremors, or profuse sweating. Detailed history taking revealed that she has had two episodes of sudden irritability, personality changes, and abnormal violent behavior that were relieved with food. After extensive endocrine hormone testing and imaging to exclude the possibility of MEN1, she was diagnosed with a 1.5-cm insulinoma in the pancreatic tail. Her blood glucose, insulin and C-peptide levels returned to normal after tumor excision.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Hypoglycemia unawareness develops after recurring episodes of hypoglycemia and increases the risk of life-threatening hypoglycemia. This case highlights the importance of identifying the underlying cause of hypoglycemia and implementing timely intervention.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fendo.2026.1802157","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T04:29:27Z","timestamp":1789964967000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Unspecific clinical manifestations of insulinoma found in preoperative testing: a case report and narrative review"],"prefix":"10.3389","volume":"17","author":[{"given":"Manqing","family":"Yu","sequence":"first","affiliation":[{"name":"Department of Endocrinology, The Affiliated Hangzhou First People\u2019s Hospital, The College of Medicine, Westlake University","place":["Hangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinlu","family":"Ji","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, The Affiliated Hangzhou First People\u2019s Hospital, The College of Medicine, Westlake University","place":["Hangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pingping","family":"Zheng","sequence":"additional","affiliation":[{"name":"The Affiliated Hangzhou First People's Hospital, The College of Medicine, Westlake University","place":["Hangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1210\/jc.2008-1410","article-title":"Evaluation and management of adult hypoglycemic disorders: an Endocrine Society Clinical Practice Guideline","volume":"94","author":"Cryer","year":"2009","journal-title":"J Clin Endocrinol Metab"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1056\/nejm199504273321707","article-title":"Hypoglycemic disorders","volume":"332","author":"Service","year":"1995","journal-title":"N Engl J Med"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1016\/j.emc.2023.06.004","article-title":"Approach to the hypoglycemic patient","volume":"41","author":"Chang","year":"2023","journal-title":"Emerg Med Clin North Am"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1210\/clinem\/dgad641","article-title":"Approach to the patient: insulinoma","volume":"109","author":"Hofland","year":"2024","journal-title":"J Clin Endocrinol Metab"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1111\/jne.13318","article-title":"European Neuroendocrine Tumor Society 2023 guidance paper for functioning pancreatic neuroendocrine tumour syndromes","volume":"35","author":"Hofland","year":"2023","journal-title":"J Neuroendocrinol"},{"key":"B6","doi-asserted-by":"publisher","first-page":"S111","DOI":"10.2337\/dc25-s006","article-title":"6. 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