Endoscopic Ultrasound-Based Differentiation of Pancreatic Neuroendocrine Tumors and Pancreatic Duct Adenocarcinoma

Summary

This study outlines a method using digital image analysis to differentiate between pancreatic neuroendocrine neoplasms (PNEN) and pancreatic ductal adenocarcinoma (PDAC).

Abstract

Endoscopic ultrasound (EUS) is one of the most critical imaging modalities for evaluating pancreatic masses, providing high-resolution visualization of the pancreas. This study aimed to assess the feasibility of digital image analysis (DIA) in differentiating pancreatic neuroendocrine neoplasms (PNEN) from pancreatic ductal adenocarcinoma (PDAC) in solid pancreatic tumors observed via EUS. A retrospective analysis was conducted on all solid pancreatic tumors examined by EUS procedures from 2018 to 2023, including cases with confirmed pathological diagnoses of PDAC and PNEN. Adobe Photoshop was used to perform DIA. The gray ratio, defined as the gray-scale ratio of the lesion to a selected background, was calculated to ensure consistency. Circularity was determined by the ratio of area to perimeter. Additionally, gray-scale standard deviations were extracted for further analysis. Three quantitative parameters from EUS images demonstrated potential for distinguishing PNEN from PDAC: circularity, gray ratio, and gray-scale standard deviation. Specifically, a circularity greater than 0.68, a gray ratio exceeding 0.40, and a gray-scale standard deviation below 12.44 were indicative of potential PNEN.

Introduction

Pancreatic cancer consists of both solid and cystic lesions and ranks among the top ten leading causes of cancer-related death worldwide¹. The most prevalent histological type of solid pancreatic tumor is pancreatic ductal adenocarcinoma (PDAC), accounting for 95% of malignant pancreatic tumors. At the time of diagnosis, approximately 80% of PDAC cases present with locally advanced disease or metastasis, with a median survival time of less than one year². Surgical and postoperative adjuvant therapies are feasible for only the remaining 20% of patients and may extend the 5-year survival rate to appro....

Protocol

The institutional review board at Ruijin Hospital approved the study [Clinical Ethics Review No. 75 (2012)], and the protocol adhered to the institutional guidelines for human care. All pancreatic lesions examined via endoscopic ultrasound (EUS) at Ruijin Hospital from 2018 to 2023 were retrospectively analyzed. Data were retrieved from the electronic medical database.

The inclusion criteria were: (1) EUS imaging showed a distinct lesion; (2) Histological diagnosis of pancreatic ductal adenocarcinoma (PDAC) or pancreatic neuroendocrine neoplasm (PNEN) was obtained. The exclusion criteria were as follows: (1) Incomplete or partially....

Results

Patients' characteristics
A total of 119 patients underwent EUS puncture and histological diagnosis, comprising 63 patients with PDAC and 54 with PNEN. The average age of the participants was 55.4 years ± 14.10 years, with 47.86% identified as male. Based on EUS features, 59 cases were located in the pancreatic head, 58 in the body or tail, and three cases involved the entire pancreas. According to the WHO staging system, more than half of the PNEN cases were classified as Stage I (62.96%, 34/54). Fo.......

Discussion

EUS is one of the most important imaging modalities for evaluating pancreatic masses, as it provides high-resolution visualization of the pancreas and enables the acquisition of adequate cytological samples through fine needle aspiration (FNA). Over the past decades, most studies have focused on improving the performance of FNA, while investigations into the echoic features of EUS imaging have remained limited. To date, studies evaluating the diagnostic value of EUS alone for differentiating PNEN in solid pancreatic tumo.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
22G Flexible Endoscopic Ultrasound Fine Needle Aspiration (EUS FNA) Needle	Boston Scientific International Medical Trading (Shanghai) Co., Ltd.	M00550010 (Single), M00550011 (Box of 5)
IBM SPSS Statistics version 22.0	IBM Corp, Armonk, NY	CRNP3ML, CIP2XML, CRNM6ML (various editions)
Linear scanning echo-endoscope, EG-530UT	Fujifilm (China) Investment Co., Ltd	EG-530UT; Balloon Pack Code: B20UT
Physiological saline (0.9% NaCl)	Chenxin Pharmaceutical Co., Ltd	Not listed (standard pharmaceutical supply)
Simethicone	Berlin-Chemie AG, Germany	Espumisan 100 mg/mL (no public catalog number)
Sodium hyaluronate	Shanghai Haohai Biotechnology Co., Ltd	Matrifill (no public catalog number)