Application and Exploration of Personalized ctDNA-MRD Detection Technology in Predicting the Efficacy of Neoadjuvant Therapy for Rectal Cancer

NCT07393048 | Recruiting

• 1 other identifier: MR-11-26-002019
• Study Type: observational
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This study is a single-center, prospective, observational clinical trial enrolling patients with locally advanced rectal cancer (cT3-4aN0M0 and cT1-4aN1-2M0). By collecting tissue and blood samples at multiple timepoints, and integrating multi-omics data including ctDNA mutations, copy number variations, and mtDNA profiles, a multi-omics model will be constructed to predict the efficacy of neoadjuvant therapy for rectal cancer.

Conditions

Locally Advanced Rectal Cancer (LARC)

Keywords

ctDNA-MRD; Rectal Cancer; Neoadjuvant Therapy; Predicting the Efficacy; Detection Technology

Outcome Measures

Primary Outcomes (1)

• Complete Response (CR) rate

  The proportion of patients confirmed to have achieved complete response after neoadjuvant therapy, as assessed by endoscopy, imaging (pelvic MRI/chest-abdominal CT), digital rectal examination, and pathological evaluation. The assessment time point corresponds to T2 (8-14 weeks after the end of neoadjuvant therapy). Complete response requires: normal mucosa on endoscopy with negative biopsy; no residual tumor on imaging; no palpable mass on digital rectal examination; and no viable tumor cells in postoperative pathology (if surgery is performed).

  Post-neoadjuvant Therapy Efficacy Assessment Time Point (within 8-12 weeks after radiotherapy completion)

Secondary Outcomes (8)

• Complete Response Rate (CR)

  Post-neoadjuvant Therapy Efficacy Assessment Time Point (within 8-12 weeks after radiotherapy completion)

• Major Pathological Response Rate (MPR)

  1 month after surgery

• Objective Response Rate (ORR)

  Post-neoadjuvant Therapy Efficacy Assessment Time Point (within 8-12 weeks after radiotherapy completion)

• Disease-Free Survival (DFS)

  Monitoring Period: Every 3 or 6 months after treatment completion, continued until 1 year.

• Overall Survival (OS)

  From the randomization date to the date of death from any cause, disease recurrence, or metastasis-whichever occurred first-assessed over the entire study period with a planned maximum follow-up of 12 months.

Study Arms (1)

Rectal Cancer ctDNA-MRD Detection Cohort

This study is an exploratory study, with an expected enrollment of 60 patients diagnosed with stage II-III rectal cancer who are scheduled to undergo neoadjuvant therapy. The sample collection and testing procedures are as follows: Before neoadjuvant therapy: Baseline endoscopic biopsy tissue or paraffin sections:1.1 Two pieces of endoscopic biopsy tissue, approximately 2 mm in diameter, are collected and placed in tissue preservation tubes.1.2 Ten unstained tissue slides are prepared. Peripheral blood collection: 10 mL of blood is collected using cell-free DNA blood collection tubes for the following assays:① ctDNA-customized MRD high-depth sequencing;② ctDNA shallow whole-genome sequencing (sWGS) for monitoring copy number variation (CNV) profiles;③ Mitochondrial DNA (mtDNA) analysis. During neoadjuvant therapy (within 2 weeks after radiotherapy completion): Peripheral blood collection: 10 mL of blood is collected using cell-free DNA blood collection tubes for the followin

Diagnostic Test: Personalized ctDNA-MRD Detection

Interventions

Personalized ctDNA-MRD Detection DIAGNOSTIC_TEST

This observational study involves collecting clinical data and biospecimens (peripheral blood and tissue samples) from participants at multiple timepoints. Personalized ctDNA-MRD detection technology, together with copy number variation and mtDNA profiling, is applied to analyze the samples. The primary goal is to predict neoadjuvant therapy efficacy by identifying biomarkers associated with key outcomes, such as tumor regression grade and pathological complete response rate. No experimental drugs or treatments are administered.

Rectal Cancer ctDNA-MRD Detection Cohort

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

"Enrolled subjects must be 18-75 years old, pathologically confirmed with rectal adenocarcinoma (MRI stage II-III), with a tumor inferior margin ≤10 cm, resectable via surgery, ECOG performance status 0-1, normal major organ function, no prior relevant treatment, ability to take oral medications, signed informed consent, and no surgical contraindications. Detailed eligibility criteria can be found in the study protocol." "Subjects with a history of drug allergy, prior cancer treatment, active or past autoimmune disease, immunodeficiency, severe heart disease, other malignant tumors (except low-risk ones) within the past five years, pregnancy or lactation, or other factors affecting safety and compliance will be excluded from this study. Detailed eligibility criteria can be found in the study protocol."

You may qualify if:

• : Signed a written informed consent form and voluntarily participated in this study
• : Aged 18-75 years, regardless of sex
• : Histopathologically confirmed rectal adenocarcinoma
• : Clinical stage II-III as assessed by MRI (according to the AJCC 8th edition)
• : Distance from the lower tumor margin to the anal verge ≤10 cm
• : Surgically resectable
• : Able to swallow tablets normally
• : ECOG PS 0-1
• : No prior antitumor therapy for rectal cancer, including radiotherapy, chemotherapy, or surgery
• : Scheduled to undergo surgical treatment after completion of neoadjuvant therapy
• : No surgical contraindications
• : Normal function of major organs, including: complete blood count, blood biochemistry, and coagulation function

You may not qualify if:

• : History of allergy to monoclonal antibodies, any component of tislelizumab, or capecitabine
• : Prior or ongoing receipt of any tumor-directed surgery, radiotherapy, chemotherapy, targeted therapy, immunotherapy, etc
• : Presence of any active autoimmune disease or history of autoimmune disease
• : History of immunodeficiency, including a positive HIV test result, other acquired or congenital immunodeficiency disorders, or history of organ transplantation or allogeneic bone marrow transplantation
• : Poorly controlled cardiac clinical symptoms or diseases, including but not limited to: heart failure of NYHA class II or above, unstable angina, myocardial infarction within the past year, or clinically significant supraventricular or ventricular arrhythmia that remains poorly controlled without or despite clinical intervention
• : Pregnant or lactating women
• : Other factors, as judged by the investigator, that may lead to premature termination of the study, such as other severe diseases (including psychiatric disorders) requiring concomitant treatment, alcohol abuse, drug abuse, family or social factors, or any condition that may affect the safety or compliance of the participant

Sponsors & Collaborators

• Beijing Friendship Hospital: lead

Study Sites (1)

Beijing Friendship Hospital

Beijing, Beijing Municipality, 100050, China

RECRUITING

Biospecimen

Retention: SAMPLES WITH DNA

Peripheral blood samples, colorectal cancer tissue samples obtained via colonoscopy, or tissue slides (white sections)

MeSH Terms

Conditions

Rectal Neoplasms

Condition Hierarchy (Ancestors)

Colorectal Neoplasms; Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Diseases; Rectal Diseases

Central Study Contacts

Yao Hongwei Professor, Doctoral Degree

CONTACT

13611015609; yaohongwei@ccmu.edu.cn

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: January 12, 2026
• First Posted: February 6, 2026
• Study Start: February 15, 2026
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): December 31, 2028
• Last Updated: April 21, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will share

Locations

CN (1)