Case Report
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Dec 15, 2024; 16(12): 4738-4745
Published online Dec 15, 2024. doi: 10.4251/wjgo.v16.i12.4738
Mixed pancreatic ductal adenocarcinoma and well-differentiated neuroendocrine tumor: A case report
Xiaofeng Zhao, Tina Bocker Edmonston, Ronald Miick, Upasana Joneja
Xiaofeng Zhao, Tina Bocker Edmonston, Ronald Miick, Upasana Joneja, Department of Pathology, Cooper University Hospital, Camden, NJ 08103, United States
Author contributions: Zhao X designed the study and collected the clinical data; Edmonston TB performed the molecular analysis; Zhao X, Miick R, and Joneja U performed the histology analysis; Zhao X, Edmonston TB, Miick R, and Joneja U wrote the manuscript; and all authors have read and approved the final manuscript.
Informed consent statement: Informed written consent was obtained from the patients for the publication of this report and any accompanying images.
Conflict-of-interest statement: The 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).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Xiaofeng Zhao, MD, PhD, Assistant Professor, Department of Pathology, Cooper University Hospital, 1 Cooper Plz, Camden, NJ 08103, United States.zhao-xiaofeng@cooperhealth.edu
Received: July 31, 2024
Revised: October 5, 2024
Accepted: October 22, 2024
Published online: December 15, 2024
Processing time: 104 Days and 11.9 Hours
Abstract
BACKGROUND

Pancreatic mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are rare malignancies affecting the pancreas. The World Health Organization defines MiNENs as neoplasms composed of morphologically recognizable neuroendocrine and non-neuroendocrine components, each constituting 30% or more of the tumor volume. Adenocarcinoma-neuroendocrine carcinoma is the most frequent MiNEN combination. A well-differentiated neuroendocrine tumor (NET) component is rarely reported in MiNENs.

CASE SUMMARY

Here we report a rare case with intermingled components of ductal adenocarcinoma and grade 1 well-differentiated NET in the pancreas. The two tumors show distinct histology and significant differentiation discrepancy (poorly differentiated high grade adenocarcinoma and well-differentiated low grade NET), and also present as metastases in separate lymph nodes. Next generation sequencing of the two components demonstrates KRAS and TP53 mutations in the ductal adenocarcinoma, but no genetic alterations in the NET, suggesting divergent origins for these two components. Although tumors like this meet the diagnostic criteria for MiNEN, clinicians often find the diagnosis and staging confusing and impractical for clinical management.

CONCLUSION

Mixed NET/non-NET tumors with distinct histology and molecular profiles might be better classified as collision tumors rather than MiNENs.

Keywords: Pancreatic mixed neuroendocrine-non-neuroendocrine neoplasms; Pancreatic adenocarcinoma; Grade 1 well-differentiated neuroendocrine tumor; Molecular profile; Collision tumor; Case report

Core Tip: Pancreatic mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are rare malignancies affecting the pancreas, recognized by the World Health Organization as neoplasms composed of morphologically recognizable neuroendocrine and non-neuroendocrine components, each constituting ≥ 30% of the tumor volume. However, whether the tumor should be classified as a MiNEN or collision tumor when there is clear divergence in histology and molecular profiles for each component is still debatable. This paper reports a rare case with high grade adenocarcinoma admixed with low grade neuroendocrine tumor in pancreas, which are demonstrated to have distinct molecular profiles. We discuss the potential impacts of tumor classification on staging and clinical management, hoping to encourage more discussions and studies on this rare entity.