Retrospective Study
Copyright ©The Author(s) 2025. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Endosc. Jun 16, 2025; 17(6): 104539
Published online Jun 16, 2025. doi: 10.4253/wjge.v17.i6.104539
Diagnostic role of endoscopic ultrasonography in defining the clinical features and histopathological spectrum of gastroenteropancreatic neuroendocrine tumors
Syedda Ayesha, Masood Muhammad Karim, Abdul Hadi Shahid, Adeel Ur Rehman, Zeeshan Uddin, Shahab Abid
Syedda Ayesha, Masood Muhammad Karim, Adeel Ur Rehman, Shahab Abid, Section of Gastroenterology, Department of Medicine, Aga Khan University, Karachi 74800, Sindh, Pakistan
Abdul Hadi Shahid, Medical College, Aga Khan University, Karachi 74800, Sindh, Pakistan
Zeeshan Uddin, Section of Histopathology, Department of Pathology and Laboratory Medicine, Aga Khan University, Karachi 74800, Sindh, Pakistan
Co-first authors: Syedda Ayesha and Masood Muhammad Karim.
Author contributions: Syedda A and Karim MM contribute equally to this study as co-first authors; Syedda A played a substantial role in identifying the topic, shaping the project's conception and design, collecting data, and drafting the manuscript; Karim MM played a substantial role in the project's conception and design, data collection, provided valuable insights into the data, and drafted the manuscript; Shahid AH assisted in shaping the project's conception and design, managed and analyzed the data, and drafted and structured the manuscript; Rehman AU contributed to interpreting the findings, provided a critical review, and proofread the manuscript; Uddin Z played a significant role in interpreting the findings of fine-needle biopsy, histological slides, and immunohistochemistry, and proofread the manuscript; Abid S supervised the project, critically reviewed the manuscript, made final edits, and ensured its accuracy and clarity with his expertise; the final draft of this work has been endorsed by all authors, who also agree to take responsibility for every aspect of the work to ensure accuracy and integrity.
Institutional review board statement: This study was reviewed and approved as exemption by the AKUH-ERC, with ethical code number 6874-25427.
Informed consent statement: Informed consent from patients was exempted in this study, as approved by the institutional ethical review committee, because the study did not involve any direct human interaction and utilized data obtained after each patient had provided written consent for treatment. Furthermore, all patient identifiers were removed during data entry, and patient confidentiality was fully maintained.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
Data sharing statement: No additional data are available.
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: Shahab Abid, Professor, Section of Gastroenterology, Department of Medicine, Aga Khan University, Stadium Road, P O Box 3500, Karachi 74800, Sindh, Pakistan. shahab.abid@aku.edu
Received: December 25, 2024
Revised: March 18, 2025
Accepted: May 7, 2025
Published online: June 16, 2025
Processing time: 167 Days and 18.9 Hours
Abstract
BACKGROUND

Neuroendocrine tumors (NETs) are rare malignancies arising from the diffuse neuroendocrine system, often in the gastroenteropancreatic (GEP) tract. GEP-NETs, primarily involving the intestines (50%) and pancreas (30%), may occasionally secrete hormones, causing syndromes. Diagnosis relies on markers like chromogranin A, synaptophysin, and Ki-67, along with imaging modalities. Rising NETs incidence is attributed to advancements in diagnostic modalities, particularly endoscopic ultrasonography (EUS). EUS demonstrates high accuracy in detecting small lesions, assessing tumor depth, and identifying locoregional lymph nodes. Despite its proven diagnostic utility, there is limited data on EUS's role in evaluating GEP-NETs in resource-constrained settings like Pakistan.

AIM

To evaluate the diagnostic role of EUS in characterizing GEP-NETs based on clinical, histopathological, tumor grading, and site-specific differences.

METHODS

This single-center retrospective descriptive study was conducted at Aga Khan University Hospital, Karachi, a tertiary care hospital, from January 2021 to December 2023. Fourteen adult patients (≥ 18 years) with suspected NETs who underwent EUS and were diagnosed via histopathology were included. Data on demographics, clinical features, radiological findings, and histopathological characteristics were collected. Descriptive analysis was performed using SPSS version 23, with descriptive statistics expressed as means ± SD for continuous variables and frequencies/percentages for categorical data.

RESULTS

A total of 14 adult GEP-NETs patients who underwent EUS were included, with a mean age of 52 ± 14 years and the majority being male (71.4%). Common clinical presentations included weight loss (85.7%) and abdominal pain (78.6%). Computed tomography scans were performed in 92.9% of cases, with pancreatic masses detected in 42.9% of patients. EUS-guided fine needle biopsy (FNB) had a 100% diagnostic yield. The pancreas was the most common tumor site (57.1%). Histopathology revealed 78.6% of cases as well-differentiated NETs with 42.9% being grade II. Metastases were seen in 57.1% of patients, with the liver being the most common site. Surgical interventions were performed in 28.6% of patients, and all patients were alive at the time of study analysis.

CONCLUSION

EUS, with accurate imaging and effective EUS-FNB, is the gold standard for GEP-NET diagnosis, aiding tumor assessment and prognosis. Larger studies are needed to validate its impact on management outcomes.

Keywords: Neuroendocrine tumors; Gastro-enteropancreatic neuroendocrine tumors; Diagnostic imaging; Endosonography; Neoplasm grading; Biopsy; Fine-needle; Endoscopic ultrasound-guided fine needle aspiration; Immunohistochemistry; Developing countries

Core Tip: Despite its proven diagnostic utility, data on endoscopic ultrasonography (EUS) in resource-constrained settings remains limited. This study evaluates the role of EUS in diagnosing gastroenteropancreatic (GEP) neuroendocrine tumors (NETs) at a tertiary hospital in Pakistan. Among 14 patients, EUS-guided fine-needle biopsy achieved a 100% diagnostic yield, with the pancreas as the most common tumor site (57.1%). Histopathology revealed 78.6% as well-differentiated NETs, and metastases were observed in 57.1% of cases, primarily to the liver. EUS proved invaluable in detecting small lesions, assessing tumor depth, and guiding management, reinforcing its role as the gold standard for GEP-NET diagnosis in low-resource settings.