{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T11:02:11Z","timestamp":1774868531662,"version":"3.50.1"},"reference-count":15,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,3,28]],"date-time":"2026-03-28T00:00:00Z","timestamp":1774656000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Reports"],"abstract":"<jats:p>Background and Clinical Significance: Pancreatic neuroendocrine tumors (pNETs) rarely exhibit intraductal growth, a pattern that may mimic intraductal papillary mucinous neoplasms (IPMNs) or pancreatic ductal adenocarcinoma (PDAC). Preoperative recognition is challenging, particularly when associated with anatomic variants such as pancreas divisum. Case Presentation: A 63-year-old man with a history of pancreatic duct dilation presented with pruritus, weight loss, and lymphadenopathy. Cross-sectional imaging revealed a cephalopancreatic mass with upstream ductal dilatation. EUS demonstrated a hypervascular lesion with intraductal extension into the dorsal duct in the setting of pancreas divisum. EUS-FNB confirmed a well-differentiated pNET (G1) with loss of DAXX expression and preserved ATRX. Ga-68 PET\/CT showed intense uptake in the primary lesion and lower-grade uptake in two additional nodules, later proven non-neoplastic. A multidisciplinary tumor board recommended preoperative optimization with somatostatin analog therapy and supervised weight reduction, followed by pylorus-preserving duodenocephalopancreatectomy. Final pathology confirmed NET G1 with intraductal growth and full concordance with preoperative EUS-FNB findings. Conclusions: in this case, a pNET showed intraductal growth within the dorsal duct in the context of pancreas divisus, further expanding the range of its reported presentations. It underscores the diagnostic value of EUS-FNB for morphologic, proliferative, and molecular characterization, and highlights the importance of multidisciplinary evaluation in guiding preoperative optimization and tailored surgical management.<\/jats:p>","DOI":"10.3390\/reports9020104","type":"journal-article","created":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T09:57:11Z","timestamp":1774864631000},"page":"104","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Rare Case of Pancreatic Neuroendocrine Tumor with Intraductal Extension in the Dorsal Duct of a Pancreas Divisum"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2365-6868","authenticated-orcid":false,"given":"Salvatore","family":"Crucill\u00e0","sequence":"first","affiliation":[{"name":"Gastroenterology and Digestive Endoscopy, Department of Medicine, University of Verona, 37134 Verona, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Asia","family":"Berlato","sequence":"additional","affiliation":[{"name":"Gastroenterology and Digestive Endoscopy, Department of Medicine, University of Verona, 37134 Verona, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4560-8741","authenticated-orcid":false,"given":"Stefano Francesco","family":"Crin\u00f2","sequence":"additional","affiliation":[{"name":"Gastroenterology and Digestive Endoscopy, Department of Medicine, University of Verona, 37134 Verona, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2474-3496","authenticated-orcid":false,"given":"Luca","family":"Landoni","sequence":"additional","affiliation":[{"name":"Department of Surgery, Pancreas Institute, University and Hospital Trust of Verona, 37134 Verona, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7813-1583","authenticated-orcid":false,"given":"Maria Cristina","family":"Conti Bellocchi","sequence":"additional","affiliation":[{"name":"Gastroenterology and Digestive Endoscopy, Department of Medicine, University of Verona, 37134 Verona, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1007\/s12022-009-9093-z","article-title":"Intraductal pancreatic neuroendocrine tumor","volume":"20","author":"Chetty","year":"2009","journal-title":"Endocr. 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