MRD Test in Common Risk Stage II Colorectal Cancer

Study Overview
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Brief Summary
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Patients with colorectal cancer who were confirmed as stage II general risk type in the postoperative pathological report began to be enrolled. Observe the sensitivity of the detection of micro-MRD before operation and the postoperative positive rate of this type of patients.

Detailed Description
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This observation part is about the patients with general risk stage II colorectal cancer who have received R0 resection after screening by nanofiltration criteria. Twenty milliliters of venous blood samples were reserved before surgery, and tumor tissue samples were reserved within 30 minutes in vitro during surgery. After the pathological diagnosis of the patients after surgery, they began to be enrolled. To observe the sensitivity of MRD detection in preoperative diagnosis of patients with general risk stage II colorectal cancer, and to study its positive rate one month and three months after operation.

Official Title
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Observation of MRD Detection for Preoperative Sensitivity and Postoperative Positive Rate in Common Risk Stage II Colorectal Cancer

Conditions
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Stage II Colorectal Cancer

Intervention / Treatment
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* Other: MRD test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-75; Pathologically confirmed rectal adenocarcinoma; Pathological differentiation is highly or moderately differentiated; The pathological stage was pT3N0, that is, invasion of the proper muscular layer of the intestinal wall without lymph node metastasis; No new adjuvant treatment before operation There was no vascular infiltration and nerve infiltration in postoperative pathology; No preoperative intestinal obstruction or tumor site perforation; No postoperative pathological margin was positive or unknown; The distance between the pathological cutting edge and the tumor was more than 1 cm; Invasion of mesentery of intestinal wall ≤ 2mm; More than 12 lymph nodes were submitted for examination; Nonlocal recurrence and distant metastasis; No multiple primary carcinoma of colon and rectum; Physical condition score PS ≤ 2 points; Patients and their families can understand and are willing to participate in this study and provide written informed consent. Exclusion Criteria: Multiple intestinal carcinomatosis Previous history of malignant tumor, There are concurrent malignant tumors in the whole body except for colorectal cancer Colorectal cancer with preoperative anti-tumor treatment Pregnant or lactating women There are serious complications during or after operation, affecting the prognosis Hepatitis B or Hepatitis C antibody positive HIV antibody positive Other diseases considered by the research doctor to affect the prognosis and survival Other conditions that the research doctor believes are not consistent with this study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: MRD test|ctDNA detection based on tumor whole exon sequencing|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Positive rate of preoperative MRD test | To observe the positive rate of preoperative MRD detection for stage II colorectal cancer | six months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Positive rate of MRD test 1 month and 3 months after operation | Observe the positive rate of MRD detection at 1 month and 3 months after operation for stage II colorectal cancer | nine months |