Early Diagnosis and Recurrence Monitoring of Colorectal Cancer

Inclusion Criteria:

1: Inclusion criteria for the case group:

1. Aged between 18 and 80 years old, regardless of gender.
2. Patients diagnosed with early colorectal cancer in our hospital, with the following specific criteria:

   1. Meet the diagnostic criteria of the Chinese Colorectal Cancer Diagnosis and Treatment Guidelines (2023 Edition) of the National Health Commission of the People's Republic of China, and be diagnosed with primary colorectal cancer by pathological tissue examination based on the imaging features of endoscopy, CT/CT enhanced scanning or MRI;
   2. Accept the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) Colorectal Cancer TNM Staging System (8th Edition, 2017) evaluation, and be evaluated as stage I or II colorectal cancer (T1-4N0M0).
   3. Have not received radiotherapy, chemotherapy, immunotherapy, surgery and other treatments.
3. No history of other malignant tumors.
4. Sign the informed consent form.

2: Inclusion criteria for participants in the control study with no obvious abnormalities in colonoscopy:

1. Aged between 18 and 80 years old, regardless of gender.
2. No abnormalities in colonoscopy results within the past 3 months.
3. No history of malignant tumors, no family history of malignant tumors (first-degree relatives, i.e. parents and/or second-degree relatives, i.e. grandfather, grandmother, uncle, etc., do not have malignant tumors).
4. No diseases such as obesity, hypertension, hyperlipidemia, metabolic syndrome, no bad living habits such as excessive drinking.
5. Voluntarily sign the informed consent form and can strictly follow the trial protocol to complete the study.

3: Inclusion criteria for patients with non-neoplastic intestinal diseases:

1. Aged between 18 and 80 years old, regardless of gender.
2. Patients diagnosed with non-neoplastic intestinal diseases such as colorectal adenoma and inflammatory bowel disease by colonoscopy and pathological examination. No history of colorectal cancer.

4: Inclusion criteria for patients with non-intestinal malignancies:

1. Aged between 18 and 80 years old, regardless of gender.
2. Meet the latest diagnostic criteria of the National Health Commission of the People's Republic of China or the Chinese Medical Association, and be diagnosed with non-intestinal malignancies such as gastric cancer, liver cancer, pancreatic cancer, esophageal cancer, etc. by pathological examination in our hospital based on imaging features of endoscopy, CT/CT enhanced scanning or MRI, combined with clinical manifestations and relevant laboratory tests. Have not received radiotherapy, chemotherapy, immunotherapy, surgery, etc. No history of colorectal cancer.

5: Inclusion criteria for the chemotherapy resistance prediction team:

1. Age between 18 and 80 years old, with no gender restrictions.
2. Patients diagnosed with colorectal cancer in our hospital, with specific criteria as follows:

   1. Meeting the diagnostic criteria of the "Diagnosis and Treatment Guidelines for Colorectal Cancer in China (2023 Edition)" issued by the National Health Commission of the People's Republic of China, and confirmed as primary colorectal cancer through pathological tissue examination based on endoscopic, CT/CT enhanced scan or MRI imaging features;
   2. Evaluated by the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) colorectal cancer TNM staging system (8th Edition, 2017), and assessed as stage II or III colorectal cancer (T1-4N1-2M0). c) Have not received radiotherapy, chemotherapy, immunotherapy, surgery or other treatments.
3. Evaluated as meeting surgical indications and planned to undergo radical surgery in three hospitals.
4. No history of other malignant tumors in the past.
5. Signed the informed consent form.

6: Inclusion Criteria for the Prediction Model of Colorectal Cancer Liver Metastasis:

1. Age between 18 and 80 years old, with no gender restrictions.
2. Patients diagnosed with colorectal cancer with liver metastasis in our hospital, with specific criteria as follows:

   1. Meeting the diagnostic criteria of the "Diagnosis and Treatment Guidelines for Colorectal Cancer in China (2023 Edition)" issued by the National Health Commission of the People's Republic of China, confirmed as primary colorectal cancer through endoscopy, liver ultrasound, CT/CT enhanced scan or MRI imaging features, and diagnosed with liver metastasis at the time of diagnosis;
   2. No previous treatment with radiotherapy, chemotherapy, immunotherapy, or surgery.
3. No history of other malignant tumors.
4. Signed informed consent form.

7: Inclusion criteria for the control group of the colorectal cancer liver metastasis cohort:

1. Age between 18 and 80 years old, with no gender restrictions.
2. Patients diagnosed with locally advanced colorectal cancer without distant metastasis in our hospital, with the following specific criteria:

   1. Meeting the diagnostic criteria of the "Diagnosis and Treatment Guidelines for Colorectal Cancer in China (2023 Edition)" issued by the National Health Commission of the People's Republic of China, and confirmed as primary colorectal cancer through pathological tissue examination based on endoscopic, CT/CT enhanced scan or MRI imaging features;
   2. Evaluated by the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) colorectal cancer TNM staging system (8th edition, 2017), the tumor invades the muscularis propria (T3), the perirectal fat (T4a), or adjacent organs (T4b), and/or has multiple local lymph node metastases (N1-2);
   3. Undergoing more than two imaging examinations (including liver ultrasound, enhanced CT, MRI, PET/CT, etc.), with no distant organ metastasis such as liver (M0) found; d) Have not received radiotherapy, chemotherapy, immunotherapy, surgery or other treatments.
3. No history of other malignant tumors in the past.
4. Signed informed consent.

Exclusion Criteria:

1. Severe complications, such as liver and kidney dysfunction (Child-Pugh C or eGFR\<30).
2. Pregnant or lactating women.
3. Those who cannot accept venipuncture, are afraid of needles and blood, or have difficulty in blood collection.
4. Those who have donated blood (including blood products) or lost blood ≥200 mL in the past 2 months, or have received blood transfusions or used blood products in the past 2 months.
5. Those who have participated in any clinical trials of drugs or medical devices in the past 3 months or those whose trial drugs have not exceeded 5 half-lives (whichever is longer).
6. Unable to cooperate with follow-up (such as mental illness, expected survival \<1 year).
7. Withdrawal or loss of follow-up during the study.
8. Incomplete information on study participants.