To evaluate the accuracy and effectiveness of a novel screening method based on plasma multi-omics combining with artificial intelligence in a large prospective cohort for the detection of colorectal cancer and advanced adenomas.

Minimally invasive detection of circulating tumor DNA (ctDNA) in peripheral blood of patients with colorectal malignancies via liquid biopsy has emerged as a promising biomarker. This is urgently needed, as conventional imaging and plasma protein-derived biomarkers lack sensitivity and specificity.The goal of this observational study is to evaluate the effectiveness and accuracy of a novel screening method based on plasma multi-omics combining with artificial intelligence in five hospitals around China for the detection of colorectal cancer and advanced adenomas.

Inclusion Criteria:

1. Inclusion criteria for colorectal cancer/advanced adenoma 1) Voluntarily participate and sign the informed consent form, and be able to cooperate with the entire research process 2) Be able to provide sufficient and qualified blood samples for this study 3) Patients with pathological diagnosis of colorectal cancer stage I-III (TNM staging according to AJCC 8th edition colorectal cancer staging system) 4) No previous cancer treatment, including chemotherapy, radiotherapy, targeted or immunotherapy, and any surgery treat 5) Advanced adenoma should at least meet one of the following conditions: ① Diameter >10mm ② Villus-tubiform adenoma ③ More than 25% of villi structure in mixed adenoma ④High-grade intraepithelial neoplasia
2. Inclusion criteria for healthy people 1) Voluntarily participate and sign the informed consent form, and be able to cooperate with the entire research process 2) Diagnosed without colorectal adenoma or cancer by colonoscopy within 12 months

Exclusion Criteria:

1. Exclusion criteria for colorectal cancer/advanced adenoma 1) Women who are pregnant or breastfeeding 2) Currently diagnosed with another cancer or have a history cancer 3) Persistent fever or receiving anti-inflammatory treatment within 14 days before blood samples are taken in this study 4) Receiving blood transfusion within 30 days 5) Receiving organ transplantation or previous non-autologous (allogeneic) bone marrow or stem cell transplantation 6) Digestive tract bleeding, obstruction, perforation and any trauma or surgery within 3 months 7) Poor physical condition, not suitable for extraction blood samples 8) Subjects who are judged by the investigator to be unsuitable to participate in this study for other reasons;
2. Exclusion criteria for healthy people 1) Women who are pregnant or breastfeeding 2) Receiving organ transplantation or previous non-autologous (allogeneic) bone marrow or stem cell transplantation 3) Have a history cancer 4) Receiving blood transfusion within 30 days 5) Poor physical condition, not suitable for extraction Blood samples 6) Diagnosed with precancerous lesions by colonoscopy.

Heathy group: Patients without colorectal adenoma or cancer examined by colonoscopy Precancerous group: Patients at least meet one of the following conditions: ① Diameter >10mm ② Villus-tubiform adenoma ③ More than 25% of villi structure in mixed adenoma ④High-grade intraepithelial neoplasia Colorectal cancer group: Patients diagnosed with adenocarcinoma by colonoscopy and histological examination.