Copyright: ©Author(s) 2026. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial (CC BY-NC 4.0) license. No commercial re-use. See permissions. Published by Baishideng Publishing Group Inc.
World J Clin Cases. Apr 26, 2026; 14(12): 120145
Published online Apr 26, 2026. doi: 10.12998/wjcc.v14.i12.120145
Published online Apr 26, 2026. doi: 10.12998/wjcc.v14.i12.120145
Size-biology paradox in ampullary tumours - large-cell neuroendocrine carcinoma of the ampulla of Vater: A case report
Evangelia Florou, Abijith Velayutham, Parthi Srinivasan, Department of Hepato-Pancreato-Biliary Surgery, King’s College Hospital, London SE5 9RS, United Kingdom
Yoh Zen, Department of Pathology, King’s College Hospital, London SE5 9RS, United King
Justin Waters, Department of Medical Oncology, Kent Oncology Centre, Maidstone and Tunbridge Wells NHS Trust, Maidstone, Kent ME16 9QQ, United Kingdom
Co-first authors: Evangelia Florou and Abijith Velayutham.
Author contributions: Florou E and Velayutham A designed the study, drafted the manuscript; Zen Y provided pathological expertise; Waters J and Srinivasan P supervised oncological management; and all authors revised and approved the final manuscript.
Informed consent statement: Written informed consent was obtained from the patient for publication of this case report and accompanying images.
Conflict-of-interest statement: All authors declare that they have no conflict of interest to disclose.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Corresponding author: Evangelia Florou, MD, Department of Hepato-Pancreato-Biliary Surgery, King’s College Hospital, Denmark Hill, London SE5 9RS, United Kingdom.
Received: February 26, 2026
Revised: March 8, 2026
Accepted: March 19, 2026
Published online: April 26, 2026
Processing time: 57 Days and 15.2 Hours
Revised: March 8, 2026
Accepted: March 19, 2026
Published online: April 26, 2026
Processing time: 57 Days and 15.2 Hours
Core Tip
Core Tip: Large-cell neuroendocrine carcinoma (LCNEC) of the ampulla of Vater is a rare and aggressive malignancy that may present as a small lesion but requires oncologically intensive management. This striking discordance between tumour size, anatomical location, and biological behaviour underpins the size-biology paradox observed in ampullary LCNEC and highlights the importance of accurate histopathological classification and multidisciplinary oncological management.