To Differentiate Focal Autoimmune Pancreatitis From Pancreatic Cancer by Endoscopic Ultrasound

Construction and Validation of a Diagnosis Model Based on Endoscopic Ultrasound Characteristics for Differentiating Between Focal Autoimmune Pancreatitis and Pancreatic Cancer

Autoimmune pancreatitis (AIP) is a special type of chronic pancreatitis mediated by autoimmunity. The classic manifestation of AIP is diffuse pancreatic enlargement, some of which are characterized by focal enlargement. Clinically, it is divided into diffuse AIP (DAIP) and focal AIP (FAIP) according to morphology. FAIP can be clinically manifested as obstructive jaundice, peripancreatic lymphadenopathy and vascular involvement, which may mimic pancreatic cancer (PC). CT/MRI is the important imaging tool for diagnosing pancreatic diseases. However, due to the overlap of the imaging features of FAIP and PC, it is challenging to differentiate the two by CT/MRI. Endoscopic ultrasound (EUS) can clearly display the pancreatic parenchyma and pancreatic duct system and has become a routine modality for the evaluation of pancreatic diseases. The aim of this study is to construct a diagnosis model for distinguishing between FAIP and PC by comparing the EUS characteristics of the two, and further validate its diagnostic efficacy.

Study Overview

• Status: Completed
• Conditions: Pancreatic Cancer; Autoimmune Pancreatitis
• Intervention / Treatment: Other: EUS for derivation sample; Other: Diagnostic imaging modalities for validation sample

Detailed Description

A derivation sample is established by retrospectively collecting the EUS images of about 100 FAIP patients and about 200 PC patients who were diagnosed for the first time in Peking Union Medical College Hospital in the past 6 years and underwent EUS at the same time. The parenchymal and ductal changes of pancreas were defined according to the Rosemont criteria. The parenchymal characteristics included hyperechoic foci/strands and lobularity, and the ductal changes included main pancreatic duct (MPD) dilation. Other EUS characteristics not included in the conventional criteria were described based on the literatures, including pancreatic diffuse hypoechogenicity, focal hypoechogenicity, pancreatic diffuse enlargement, focal enlargement, peripancreatic hypoechoic margin, common bile duct (CBD) dilation, bile duct wall thickening, lymphadenopathy and vessel involvement. The EUS characteristics of the two groups of patients are included in the multivariate stepwise logistic regression and receiver operating characteristics (ROC) analyses to construct a differential diagnosis model in derivation sample. Further, the differential diagnosis model will be prospectively validated by calculating the sensitivity and specificity in about 90 patients who are going to undergo EUS due to the difficulty in distinguishing between FAIP and PC. Diagnosis of AIP meets the revised Mayo clinic criteria (revised HISORt criteria) including features of histology, imaging, serology, other organs involvement and response to steroid therapy. Diagnosis of pancreatic duct adenocarcinoma is confirmed by surgical pathology or by cytology/histology after EUS-guided fine needle aspiration or biopsy.

• Study Type: Observational
• Enrollment (Actual): 286

Contacts and Locations

Study Locations

• China
  • Beijing
    • Beijing, Beijing, China, 100730
      • Peking Union Medical College Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: No older than 75 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

In derivation sample, the patients conclusively diagnosed as FAIP or PC are retrospectively collected.

In validation sample, the patients with difficulty in distinguishing between FAIP and PC are prospectively enrolled. In the end, the patient with a diagnosis that is neither FAIP nor PC and the patient without conclusive diagnosis are withdrawn from the study.

Description

Inclusion Criteria:

• Patients with difficulty in distinguishing between FAIP and PC

Exclusion Criteria:

• Referred patients with a history of having being conclusively diagnosed as AIP or PC; Patients with DAIP; Patients with alcoholic pancreatitis, hypertriglyceridemia pancreatitis or pancreatitis due to gallstones; Patients with pancreatic cystic tumors, pancreatic neuroendocrine tumors or solid pseudopapillary tumors of pancreas; Patients who cannot undergo EUS due to unsuitable conditions.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Other

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Derivation sample; The patients conclusively diagnosed as FAIP or PC are retrospectively collected.	Other: EUS for derivation sample; Endoscopic ultrasound was performed.
Validation sample; The patients with difficulty in distinguishing between FAIP and PC are prospectively enrolled.	Other: Diagnostic imaging modalities for validation sample; Endoscopic ultrasound and other imaging modalities such as CT, MRI, or PET-CT are performed.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To construct a diagnosis model for distinguishing FAIP from PC and further validate its efficacy	Score is assigned to each predictor based on the odd ratio (OR) value, individual risk is estimated based on the sum of weighted score for each predictor and optimal cut-off point is obtained based on receiver operating characteristic (ROC) analysis. Sensitivity and specificity were used to assess the diagnostic efficacy.	1 week after the diagnosis is conclusive

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Compare the efficacy of EUS based on the model with that of CT/MRI/PET-CT in differentiating between FAIP and PC	Sensitivity and specificity were used to assess the diagnostic efficacy	1 week after the diagnosis is conclusive

Collaborators and Investigators

• Sponsor: Peking Union Medical College Hospital
• Collaborators: The Second Hospital of Hebei Medical University; Tongji Hospital; Qilu Hospital of Shandong University; Wuhan Union Hospital, China; Tianjin Medical University General Hospital
• Investigators: Principal Investigator: Tao Guo, MD, Peking Union Medical College Hospital

Publications and helpful links

General Publications

• Hart PA, Zen Y, Chari ST. Recent Advances in Autoimmune Pancreatitis. Gastroenterology. 2015 Jul;149(1):39-51. doi: 10.1053/j.gastro.2015.03.010. Epub 2015 Mar 12.
• Kamisawa T, Okamoto A. Autoimmune pancreatitis: proposal of IgG4-related sclerosing disease. J Gastroenterol. 2006 Jul;41(7):613-25. doi: 10.1007/s00535-006-1862-6.
• Miyabe K, Zen Y, Cornell LD, Rajagopalan G, Chowdhary VR, Roberts LR, Chari ST. Gastrointestinal and Extra-Intestinal Manifestations of IgG4-Related Disease. Gastroenterology. 2018 Oct;155(4):990-1003.e1. doi: 10.1053/j.gastro.2018.06.082. Epub 2018 Sep 12.
• Muhi A, Ichikawa T, Motosugi U, Sou H, Sano K, Tsukamoto T, Fatima Z, Araki T. Mass-forming autoimmune pancreatitis and pancreatic carcinoma: differential diagnosis on the basis of computed tomography and magnetic resonance cholangiopancreatography, and diffusion-weighted imaging findings. J Magn Reson Imaging. 2012 Apr;35(4):827-36. doi: 10.1002/jmri.22881. Epub 2011 Nov 8.
• Gardner TB, Levy MJ. EUS diagnosis of chronic pancreatitis. Gastrointest Endosc. 2010 Jun;71(7):1280-9. doi: 10.1016/j.gie.2010.02.038. No abstract available.
• Hoki N, Mizuno N, Sawaki A, Tajika M, Takayama R, Shimizu Y, Bhatia V, Yamao K. Diagnosis of autoimmune pancreatitis using endoscopic ultrasonography. J Gastroenterol. 2009;44(2):154-9. doi: 10.1007/s00535-008-2294-2. Epub 2009 Feb 13.
• Chari ST, Takahashi N, Levy MJ, Smyrk TC, Clain JE, Pearson RK, Petersen BT, Topazian MA, Vege SS. A diagnostic strategy to distinguish autoimmune pancreatitis from pancreatic cancer. Clin Gastroenterol Hepatol. 2009 Oct;7(10):1097-103. doi: 10.1016/j.cgh.2009.04.020. Epub 2009 May 4.

Study record dates

Study Major Dates

• Study Start (Actual): May 11, 2021
• Primary Completion (Actual): September 30, 2024
• Study Completion (Actual): December 30, 2024

Study Registration Dates

• First Submitted: April 4, 2021
• First Submitted That Met QC Criteria: April 4, 2021
• First Posted (Actual): April 8, 2021

Study Record Updates

• Last Update Posted (Actual): May 31, 2025
• Last Update Submitted That Met QC Criteria: May 27, 2025
• Last Verified: May 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Endocrine System Diseases; Pathologic Processes; Neoplasms by Site; Neoplasms; Chronic Disease; Disease Attributes; Autoimmune Diseases; Immune System Diseases; Digestive System Neoplasms; Digestive System Diseases; Endocrine Gland Neoplasms; Pancreatic Diseases; Pancreatitis, Chronic; Autoimmune Pancreatitis; Pancreatitis; Pancreatic Neoplasms
• Other Study ID Numbers: EUS-AIP-PC-1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The protocol of the study is private.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No