Study on the Diagnostic Accuracy of Endoscopic Ultrasound for Submucosal Masses of Colorectal Cancer
Conditions: Colorectal Subepithelial Lesions
Sponsor: Run-hua Li

 
 
 
 
Study on the Diagnostic Accuracy of Endoscopic Ultrasound for Colorectal 
Subepithelial Lesions 
 
NCT number：not yet assigned 
Document date：2023.11.20 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
1. Background 
On endoscopic ultrasound (EUS), the normal intestinal wall is typically 
visualized as a five-layer structure with alternating hyperechoic and hypoechoic 
layers, corresponding to the superficial mucosal interface, deep mucosa/muscularis 
mucosa, submucosa, muscularis propria, and serosa. For subepithelial lesions (SELs), 
EUS can measure lesion size and assess sonographic features such as margins, 
homogeneity, and acoustic shadowing. It also provides information on the layer of 
origin, lesion location, and relationship to surrounding tissues. By integrating these 
findings, EUS may help predict pathological nature and guide subsequent 
management. 
However, compared with final histopathology, the reported diagnostic accuracy of 
EUS for gastrointestinal SELs is approximately 43%–79%, which may not fully meet 
current clinical needs. 
 
2. Objectives 
2.1 Primary Objective 
To identify factors associated with the coincidence (concordance) between EUS 
diagnosis and pathological diagnosis for colorectal subepithelial lesions. 
 
3. Endpoints 
3.1 Primary Endpoint 
Coincidence rate between EUS diagnosis and pathological diagnosis. 
 

4. Study Design 
This is a single-center, retrospective, observational study. All patients who 
underwent colorectal EUS at Shenzhen Hospital of Southern Medical University 
between 2015 and 2023 will be screened, and their endoscopy/EUS reports and 
pathology reports will be retrospectively reviewed and analyzed. 
If a patient had two or more colorectal lesions evaluated by EUS, lesions at different 
sites will be treated as independent EUS examinations. Only SEL cases with 
histopathologic confirmation will be included for further analysis. 
During the study, no randomization will be performed and no protocol-driven 
treatment will be administered or provided. When clinically indicated, treatment 
decisions and treatment selection will be made at the discretion of the treating 
physician. 
 
5. Study Population 
The study population consists of patients with colorectal subepithelial lesions. 
5.1 Diagnostic Criteria 
Diagnosis of colorectal submucosal tumors/subepithelial lesions will be based on 
the Chinese expert consensus on endoscopic diagnosis and treatment of 
gastrointestinal submucosal tumors (2023 edition). 
5.2 Inclusion Criteria 
1. 
Patients admitted to Shenzhen Hospital of Southern Medical 
University from 2015 to 2023 who underwent colorectal EUS. 
2. 
Patients diagnosed with colorectal submucosal tumors (subepithelial 
lesions) according to the Chinese expert consensus on endoscopic diagnosis 
and treatment of gastrointestinal submucosal tumors (2023 edition) and related 
criteria. 

5.3 Exclusion Criteria 
1. 
Patients whose EUS diagnosis indicated non-submucosal tumors 
(i.e., not consistent with submucosal tumors/subepithelial lesions). 
5.4 Withdrawal and Loss to Follow-up 
All enrolled participants have the right to withdraw from this study at any time. 
Reasons for withdrawal include: 
• 
Participant requests withdrawal and does not wish to continue 
participation; 
• 
Participant is lost to follow-up; 
• 
Participant refuses further follow-up; 
• 
Other reasons deemed by the investigator to make the participant 
unsuitable to continue in the study. 
Participants who withdraw during the study will be considered dropouts. After 
dropout, efforts should be made to contact the participant to complete assessments as 
feasible and to complete the study summary page. 
 
6. Methods and Procedures 
As this is an observational study, no additional study visits, laboratory testing, or 
assessments beyond routine clinical practice are required. Treating physicians will 
determine clinical management according to product labeling and local standards of 
care. Investigators will review medical history and laboratory reports and determine 
eligibility based on the inclusion and exclusion criteria. 
A waiver of informed consent will be requested because the samples and 
information are derived from medical records and specimens collected during routine 
clinical care; the study poses no more than minimal risk to participants; the waiver 

will not adversely affect participants’ rights or welfare; obtaining consent would make 
the study impracticable; and participants’ privacy and personal identifiers will be 
protected. 
The number and timing of clinical visits will be determined by physicians 
according to local routine practice. 
6.1 Informed Consent and Enrollment 
A waiver of written informed consent will be applied for. Participants who meet 
all other inclusion/exclusion criteria will be considered enrolled. 
6.2 Participant Identification Number 
Each participant will be assigned a unique identification number in chronological 
order based on the date of examination. All study documents (e.g., case report forms, 
clinical records) will use this identification number. In accordance with data privacy 
regulations, the identification number must not include combinations that could 
identify the participant (e.g., initials plus date of birth should not be used together). 
6.3 Data Source / Data Collection Process 
Study data will be obtained by extracting routine clinical medical records of 
enrolled participants. Investigators will enter information from source medical records 
into study record forms throughout the monitoring period. 
6.4 Data Collection Items 
1. 
Demographics: age, sex, initials; 
2. 
Lesion location and size (maximum diameter); 
3. 
EUS echogenic features, layer-related characteristics, EUS diagnosis 
(primary diagnosis), operator, and device information; 
4. 
Pathology acquisition method, pathological layer, and pathological 
diagnosis. 

 
7. Criteria for Study Termination / Suspension 
7.1 The sponsor has the right to terminate or suspend the study. Before 
termination/suspension, the sponsor must notify the investigator, the ethics 
committee, and relevant regulatory authorities and provide the rationale. If the study 
is terminated/suspended early, restarting the study requires ethics committee approval. 
7.2 Termination or suspension as required by the ethics committee. 
 
8. Study Completion 
The study will be completed when data collection reaches the predefined time 
interval. 
 
9. Data Management 
9.1 Data Management Procedures 
1. 
Investigators must ensure data are truthful, complete, and accurate. 
2. 
Any correction to study records must be made by a single line 
through the original entry, with the corrected data annotated, the reason 
documented, and the investigator’s signature and date provided; erasing or 
overwriting original records is not permitted. 
3. 
Required laboratory examination items should be complete as 
applicable in routine care. 
9.2 Data Recording and Document Retention 
Participant data in case report forms will be recorded using coded identifiers; 
participants may only be identifiable via the participant code or initials. 
This study will use an Excel database for data management, with double data 

entry. After source data verification and confirmation of data integrity, the database 
will be locked. After database lock, the analysis dataset will be exported for statistical 
analysis. Locked data cannot be edited. If issues are identified after database lock, 
they may be corrected within the statistical analysis program after confirmation. 
 
10. Statistical Analysis 
10.1 Sample Size Determination 
This is a single-center, retrospective, observational study. One-way analysis of 
variance (ANOVA) will be used to explore factors associated with concordance 
versus non-concordance between EUS diagnosis and pathological diagnosis. Using 
G*Power (version 3.1.9.7) with an effect size of 0.25, α = 0.05, power (1−β) = 0.80, 
10 predictors, and 2 groups, the required sample size was calculated to be 269 cases. 
10.2 Statistical Methods 
Analyses will include case distribution, demographic characteristics and baseline 
analyses, and outcome analyses. 
10.3 Statistical Software and General Requirements 
• 
Statistical analyses will be performed using SPSS. 
• 
Continuous variables will be summarized using mean, standard 
deviation, median, minimum, and maximum values. 
• 
Categorical variables will be summarized using frequencies and 
percentages. 
• 
One-way ANOVA will be used to evaluate differences in potential 
factors between the concordant and non-concordant groups. 
• 
Multivariable logistic regression will be performed to identify key 
factors independently associated with diagnostic concordance. 

 
11. Study Management 
11.1 Compliance With Regulations and Standards 
1. 
Investigators will implement quality control (QC) and quality 
assurance (QA) systems in accordance with standard operating procedures 
(SOPs). 
2. 
Source documents must comply with relevant regulations and 
standards. 
3. 
Laboratory test results must be accurate and reliable. 
4. 
All observations and findings will be verified to ensure data 
reliability. 
5. 
A complete study organizational structure will be established with 
clearly defined responsibilities at each level. 
6. 
The principal investigator (PI) will be responsible for overall quality 
control and ensuring that all personnel fulfill their responsibilities. 
7. 
The PI will be responsible for study protocol development and 
related documents; the PI will prepare the study summary report after study 
completion. 
8. 
Designated personnel will develop the study implementation 
procedures and SOPs for use during the study. 
9. 
Before study initiation, the study team will organize training on the 
protocol; all study personnel must receive GCP training. 
10. Physicians and nurses participating in the study must strictly follow 
the protocol and procedures and must not modify them arbitrarily. 
11. Designated statisticians will be responsible for comprehensive 

statistical processing of the study data. 
11.2 Protection of Participant Privacy 
All participant data collected during the study will be entered into a computer 
system for confidential storage and analysis. If necessary, relevant authorities may 
audit the records to verify the authenticity, accuracy, and completeness of the data. 
Study results may be published in academic journals; however, participant names will 
not be disclosed, and participant privacy will be protected. 
11.3 Problems During the Study and Corrective Measures 
1. 
Protocol amendments: After ethics approval, any revision requires a 
“protocol amendment statement” signed by the PI. Amendments may be made 
only after consultation and agreement between the investigators and the 
sponsor (and/or the registration applicant, as applicable). 
2. 
After revision, the amended protocol must be submitted to the ethics 
committee for review and approval prior to implementation. 
3. 
No study personnel may deviate from the protocol. 
11.4 Quality Control and Quality Assurance 
11.4.1 Quality Assurance 
The sponsor and any collaborating organizations entrusted by the sponsor with 
all or part of the study responsibilities shall establish their own QA systems, fulfill 
their responsibilities, and strictly adhere to the protocol and applicable SOPs to ensure 
the implementation of QC/QA systems. 
11.4.2 Quality Assurance for Study Conduct 
Prior to study initiation, investigators will receive training on the protocol to 
ensure full understanding of the study procedures and endpoints. QC personnel will 
verify basic study conditions to ensure that the site can meet protocol requirements. 
During the study, investigators will follow institutional SOPs and the protocol, 

perform clinical procedures accordingly, and maintain true, timely, complete, and 
standardized records. QC personnel will review study processes and corresponding 
source documents. After study completion, study documents will be compiled, 
checked by QC personnel, and archived. The institutional QA department may 
conduct feasibility audits; when noncompliance is identified, investigators and 
responsible personnel will be notified to implement corrective actions and to track the 
completion of corrections. 
11.4.3 Expected Study Timeline and Completion Dates 
• 
October 2023 to January 2024: completion of data collection 
• 
January 2024 to April 2024: completion of data analysis 
11.5 Responsibilities of Each Party and Other Related Work 
1. 
Sponsor responsibilities: The sponsor is responsible for initiating, 
applying for, and organizing this study, and for providing study funding. 
2. 
Investigator responsibilities: Investigators will conduct the study 
in accordance with the Declaration of Helsinki and relevant regulatory, ethical, 
and scientific principles, and in accordance with the protocol. Investigators 
should be familiar with procedures and requirements for reporting serious 
adverse events (SAEs) and record/report such events as required. Investigators 
will enter data into study records accurately, completely, timely, and legally, 
and will accept monitoring/audits by sponsor- or CRO-appointed 
monitors/auditors and inspections by regulatory authorities to ensure study 
quality. 
3. 
Publication of study data: The sponsor holds exclusive rights to 
the study data. Unless written permission is obtained from the sponsor or 
specified in a collaboration agreement, no publication should be made in an 
individual capacity prior to completion of the final report. The sponsor has 
final authority over manuscripts and publications. 

11.6 Human Genetic Resources 
The collection, acquisition, trade, export, or cross-border transfer of human 
genetic resources shall comply with the Interim Measures for the Administration of 
Human Genetic Resources (Guo Ban Fa [1998] No. 36). 
 
12. Research-Related Ethics 
12.1 Ethics Committee 
Before study initiation, investigators must submit the investigator’s brochure (if 
applicable), study protocol, request for waiver of informed consent, and any other 
participant-related information to the ethics committee for review and approval. Any 
protocol amendments must be approved again by the ethics committee. 
12.2 Informed Consent 
Qualified investigators must explain the nature and purpose of the study, 
procedures, expected duration, potential risks and benefits, and any possible 
discomfort to each participant as part of the informed consent process. Each 
participant must understand that participation is voluntary and that they may withdraw 
from the study at any time without affecting subsequent treatment or the relationship 
with their treating physician. 
The informed consent form should follow a standard format and use non-technical 
language as much as possible. Each informed consent form must include the above 
content and a statement of voluntariness, and must be submitted to the ethics 
committee for approval. 
A waiver of informed consent will be requested because study samples and 
information are derived from medical records and specimens collected during routine 
clinical care; the study poses no more than minimal risk; the waiver will not adversely 
affect participants’ rights or welfare; and obtaining consent would make the study 
impracticable. Participant privacy and personal identifiers will be protected. 

12.3 Other 
None. 
 
13. References 
1. 
Kida M, Kawaguchi Y, Miyata E, Hasegawa R, Kaneko T, Yamauchi 
H, Koizumi S, Okuwaki K, Miyazawa S, Iwai T, Kikuchi H, Watanabe M, 
Imaizumi H, Koizumi W. Endoscopic ultrasonography diagnosis of 
subepithelial 
lesions. 
Dig 
Endosc 
2017; 
29 
(4): 
431-443. 
doi: 
10.1111/den.12854. 
2. 
2. Kim TO. Colorectal Subepithelial Lesions. Clinical endoscopy 
2015; 48 (4): 302-307. doi: 10.5946/ce.2015.48.4.302. 
3. 
Surgery Group of the Chinese Society of Digestive Endoscopy, 
Chinese Society of Digestive Endoscopy; NOTES Group of the Chinese 
Society of Digestive Endoscopy; Digestive Endoscopy Professional 
Committee of the Endoscopist Branch of the Chinese Medical Doctor 
Association; Gastrointestinal Surgery Group of the Surgery Branch of the 
Chinese Medical Association. Chinese expert consensus on endoscopic 
diagnosis and treatment of gastrointestinal submucosal tumors (2023 edition). 
Chin J Dig Endosc. 2023;40(4):253–263. doi:10.3760/cma.j.cn321463-
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