Retrospective Analysis of Early Gastric Cancer Patients Based on Prospective Clinical Dataset

Establishing an Innovative Cohort for Chinese Early Gastric Cancer Patients Based on the National Clinical Research Center for Digestive Diseases Prospective Database: A Retrospective Study

The goal of this retrospective observational cohort study is to describe the real-world clinicopathological characteristics, evolving treatment patterns, and long-term oncological outcomes of early gastric cancer (EGC) patients in China, utilizing a large prospective clinical database.

The main questions it aims to answer are:

How do different treatment modalities, including endoscopic resection, laparoscopic surgery, open surgery, and combined laparoscopic-endoscopic approaches, influence the long-term survival (Overall Survival and Disease-Free Survival) and recurrence patterns in Chinese EGC patients? What are the key clinicopathological factors affecting prognosis in this population? This study will retrospectively enroll approximately 5000 patients with histopathologically confirmed gastric adenocarcinoma staged as early gastric cancer (per AJCC 8th edition) from the information database of the National Clinical Research Center for Digestive Diseases. Researchers will systematically collect baseline demographics, treatment details, surgical complications, pathological staging, and longitudinal follow-up data (up to 10 years post-surgery) for all eligible patients. By comparing the short-term safety profiles and long-term survival benefits across different treatment groups and identifying risk factors for recurrence, this study aims to provide high-quality, China-specific evidence to guide standardized and individualized clinical decision-making for early gastric cancer.

Study Overview

• Status: Recruiting
• Conditions: Early Gastric Cancer
• Intervention / Treatment: Other: Clinical Data Collection

• Study Type: Observational
• Enrollment (Estimated): 5000

Contacts and Locations

• Study Contact: Name: Zhi zheng, Attending surgon; Phone Number: +86-13811132175; Email: zhengzhi@ccmu.edu.cn

Study Locations

• China
  • Beijing, China
    • Recruiting
    • Beijing Friendship Hospital, Capital Medical University
    • Contact: Zhi Zheng, Attending surgon; Email: zhengzhi@ccmu.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study population will be derived from the information database of the National Clinical Research Center for Digestive Diseases at Beijing Friendship Hospital, Capital Medical University. This retrospective cohort will include approximately 5000 patients who were diagnosed with early gastric cancer. All patients included in the database during this period who meet the eligibility criteria will be consecutively enrolled. The source population consists of patients who visited Beijing Friendship Hospital for the diagnosis and treatment of gastric cancer. The database contains comprehensive clinicopathological data, treatment details, and longitudinal follow-up information for all enrolled patients. Beijing Friendship Hospital is a large tertiary referral center in China serving a broad geographic catchment area, and the study population is expected to reflect a diverse range of patient demographics and clinical presentations.

Description

Inclusion Criteria:

• patients aged between 18 and 90 years;
• preoperative endoscopic biopsy-confirmed gastric adenocarcinoma;
• clinical stage early gastric (cT1NxM0) cancer according to the AJCC 8th edition TNM staging system;
• patients who have signed a broad informed consent.
• Received primary treatment (including endoscopic resection, laparoscopic surgery, open surgery, or combined laparoscopic-endoscopic approach) at Beijing Friendship Hospital.

Exclusion Criteria:

• pregnant or breastfeeding women;
• Preoperative or intraoperative diagnosis remained indeterminate due to insufficient pathological or imaging evidence, such that the patient could not be clearly classified as early gastric cancer prior to treatment;
• Critical clinical data were severely incomplete or missing；
• Completely lost to follow-up with no available information to confirm survival status.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Early Gastric Cancer Cohort; A retrospective cohort of approximately 5000 patients with histopathologically confirmed early gastric cancer (AJCC 8th edition) treated at Beijing Friendship Hospital. Data were extracted from the National Clinical Research Center for Digestive Diseases information database.	Other: Clinical Data Collection; Retrospective collection of clinicopathological characteristics, treatment details, and long-term follow-up data from electronic medical records and the institutional database.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Disease-Free Survival	Disease-free survival is defined as the time from the date of surgery to the date of first documented tumor recurrence, metastasis, or death from any cause.	From date of surgery to up to 10 years post-surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall Survival	Overall survival is defined as the time from the date of surgery to death from any cause.	From date of surgery to up to 10 years post-surgery
Recurrence-Free Survival	Recurrence-free survival is defined as the time from the date of surgery to the first occurrence of disease recurrence.	From the date of surgery to 10 years post-surgery
Progression-Free Survival	Progression-free survival is defined as the time from the date of surgery to the first occurrence of either disease progression or death from any cause. Disease progression includes recurrence, metastasis, or progression of residual disease.	From the date of surgery to 10 years post-surgery
30-Day Postoperative Complications	Incidence and severity of complications occurring within 30 days following surgery, graded according to the Clavien-Dindo classification.	From the date of surgery to 30 days post-surgery
30-Day Postoperative Mortality	All-cause mortality occurring within 30 days after surgery, ascertained from medical records and follow-up data.	From the date of surgery to 30 days post-surgery
Unscheduled Second Surgery Rate	Rate of unscheduled reoperation within 30 days after the initial surgery, identified from surgical records and inpatient documentation.	From the date of surgery to 30 days post-surgery
Unplanned Return to Hospital Rate	Rate of unplanned hospital readmission within 30 days after discharge following the initial surgery, identified from readmission records.	From the date of surgery to 30 days post-surgery
Operation Time	Total duration of the surgical procedure, extracted from operative records.	At the time of surgery
Intraoperative Blood Loss	Estimated total volume of blood loss during the surgical procedure, extracted from operative records and anesthesia documentation.	At the time of surgery
Postoperative Length of Stay	Total number of days from the date of surgery to hospital discharge, extracted from inpatient medical records.	From date of surgery until date of hospital discharge, assessed up to 2 weeks
Preoperative Endoscopic Tumor Size	Maximum diameter of the primary tumor (in millimeters) measured by preoperative gastroscopy.	From 30 days prior to surgery to the date of surgery
Preoperative Endoscopic Macroscopic Type	Macroscopic type of the primary tumor assessed by preoperative gastroscopy, classified as elevated (0-I), flat (0-IIa, IIb, IIc), or depressed (0-III) types according to the Paris classification.	From 30 days prior to surgery to the date of surgery
Preoperative CT-Determined Tumor Invasion Depth (cT)	Depth of tumor invasion assessed by preoperative contrast-enhanced CT, categorized as cT1, cT2, cT3, or cT4 according to the AJCC 8th edition TNM staging system.	From 30 days prior to surgery to the date of surgery
Preoperative CT-Determined Lymph Node Status (cN)	Lymph node metastasis status assessed by preoperative contrast-enhanced CT, categorized as cN0, cN1, cN2, or cN3 according to the AJCC 8th edition TNM staging system.	From 30 days prior to surgery to the date of surgery
Preoperative CT Suspicious Lymph Node Count	The number of suspicious metastatic lymph nodes identified during the preoperative enhanced CT examination.	From 30 days prior to surgery to the date of surgery
Pathological Tumor Invasion Depth (pT)	Pathological depth of tumor invasion assessed according to AJCC 8th edition pT category (pT1a, pT1b, pT2, pT3, or pT4) based on postoperative histopathological examination of the resected specimen.	From date of surgery to 7 days post-surgery
Pathological Lymph Node Status (pN)	Pathological lymph node metastasis status assessed according to AJCC 8th edition pN category (pN0, pN1, pN2, or pN3) based on postoperative histopathological examination.	From date of surgery to 7 days post-surgery
Number of Lymph Nodes Examined	Total number of lymph nodes retrieved and examined from the resected specimen.	From date of surgery to 7 days post-surgery
Number of Positive Lymph Nodes	Total number of lymph nodes with pathologically confirmed metastasis.	From date of surgery to 7 days post-surgery
Anatomical Location of Metastatic Lymph Nodes	Anatomical distribution of pathologically confirmed metastatic lymph nodes identified in the resected specimen, categorized by lymph node station (e.g., No.1, No.3, No.4sb, No.7, etc.) according to the Japanese Gastric Cancer Association (JGCA) classification system. Data will be extracted from postoperative pathology reports.	From date of surgery to 7 days post-surgery
Lymph Node Metastasis Rate	Proportion of positive lymph nodes among total lymph nodes examined (number of positive lymph nodes / total lymph nodes examined × 100%).	From date of surgery to 7 days post-surgery
Histological Differentiation	Histological differentiation of gastric adenocarcinoma, categorized as well-differentiated, moderately-differentiated, poorly-differentiated, or undifferentiated, based on postoperative pathology.	From date of surgery to 7 days post-surgery
Lymphovascular Invasion	Presence or absence of lymphatic and/or vascular invasion assessed by postoperative histopathological examination.	From date of surgery to 7 days post-surgery
Perineural Invasion	Presence or absence of perineural invasion assessed by postoperative histopathological examination.	From date of surgery to 7 days post-surgery
R0 Resection Rate	Proportion of patients with no residual tumor microscopically confirmed on both the primary tumor resection margins and resected lymph nodes, assessed by postoperative pathological examination.	From date of surgery to 7 days post-surgery
Gastric Emptying Scintigraphy	It is evaluated by gastric emptying half-time (GET₁/₂) measured via radionuclide scintigraphy.	From 30 days prior to surgery to 10 years post-surgery
Helicobacter pylori Infection Status	Helicobacter pylori infection status determined by ¹³C/¹⁴C urea breath test.	From 30 days prior to surgery to 10 years post-surgery
EORTC QLQ-C30	The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30(EORTC-QLQ-C30) includes 30 items measuring functional, symptomatic, and global quality-of-life domains. Scores are transformed to a 0-100 scale, with higher scores indicating better quality of life.	From 30 days prior to surgery to 10 years post-surgery
EORTC QLQ-STO22	The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Stomach Cancer Module 22(EORTC-QLQ-STO22) supplement contains 22 items assessing symptoms and concerns specific to gastric cancer. Scores are transformed to a 0-100 scale, with higher scores indicating greater symptom burden.	From 30 days prior to surgery to 10 years post-surgery
PGSAS-45	The Postgastrectomy Syndrome Assessment Scale 45(PGSAS-45), consisting of 45 items, will be used to comprehensively evaluate postgastrectomy symptoms, digestive status, and daily life functions. All subscale scores are linearly transformed to a 0-100 range. For symptom-related subscales, higher scores indicate greater symptom burden; for functional and quality of life subscales, higher scores indicate better functioning or quality of life.	From 30 days prior to surgery to 10 years post-surgery
Serum Albumin		From 30 days prior to surgery to 10 years post-surgery
Serum Total Protein		From 30 days prior to surgery to 10 years post-surgery
Hemoglobin		From 30 days prior to surgery to 10 years post-surgery
Prognostic Nutritional Index (PNI)	It is a combined score based on serum albumin level and total lymphocyte count. It is calculated as 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (cells/μL). Higher scores indicate better nutritional and immunological status.	From 30 days prior to surgery to 10 years post-surgery
Inflammatory marker	It will be measured by serum C reactive protein (CRP) level.	From 30 days prior to surgery to 10 years post-surgery
Carcinoembryonic Antigen (CEA)		From 30 days prior to surgery to 10 years post-surgery
Carbohydrate Antigen 19-9 (CA19-9)		From 30 days prior to surgery to 10 years post-surgery
Carbohydrate Antigen 72-4 (CA72-4)		From 30 days prior to surgery to 10 years post-surgery
Alpha-Fetoprotein (AFP)		From 30 days prior to surgery to 10 years post-surgery
Carbohydrate Antigen 125 (CA125)		From 30 days prior to surgery to 10 years post-surgery
Time to First Flatus	Time from the date of surgery to the first passage of flatus, indicating recovery of gastrointestinal motility. Data will be extracted from postoperative recovery records.	From date of surgery until date of hospital discharge, assessed up to 2 weeks
Resumption of Oral Intake	Time from the date of surgery to the resumption of oral intake (liquid or solid diet), extracted from postoperative dietary records.	From date of surgery until date of hospital discharge, assessed up to 2 weeks
Overall Hospitalization Cost		From the time of admission to the time of discharge, assessed up to 3 weeks

Collaborators and Investigators

• Sponsor: Beijing Friendship Hospital

Study record dates

Study Major Dates

• Study Start (Actual): May 8, 2026
• Primary Completion (Estimated): May 8, 2027
• Study Completion (Estimated): June 8, 2027

Study Registration Dates

• First Submitted: July 31, 2026
• First Submitted That Met QC Criteria: July 31, 2026
• First Posted (Actual): August 5, 2026

Study Record Updates

• Last Update Posted (Actual): August 5, 2026
• Last Update Submitted That Met QC Criteria: July 31, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Stomach Diseases; Stomach Neoplasms
• Other Study ID Numbers: 2026-P2-266-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No