The primary objective is to determine the diagnostic sensitivity and specificity of the newly developed multitarget FIT-DNA Colorectal Cancer (CRC) screening test (ColoClear) for detecting advanced neoplasia (including colorectal cancer and advanced adenomas) in high risk patients, using colonoscopy as the reference method. The secondary objective is to compare the screening performance of the multitarget FIT-DNA test with commercially available FIT (Fecal Immunochemical Test) assay in detecting advanced neoplasia.

The study will be carried out in 8 tier-3A hospitals throughout China. Patients who are at high risk of developing colorectal cancer and willing to conduct colonoscopy examination will be asked to collect stool sample prior to bowl preparation for multitarget FIT-DNA test and commercially available FIT assay. Colonoscopy and histopathologic examination are used as reference.

Inclusion Criteria:

• Willing to provide written consent
• Able to provide stool sample

For high risk CRC screening group:

• Scheduled for colonoscopy voluntarily or by physician prescription
• CRC high risk profile as defined below:
• History of FIT positivity
• Family history of CRC
• Any of two of the following clinical symptoms: chronic constipation/diarrhea, stool with mucous, chronic appendicitis, chronic bilary track diseases, mental stress

For CRC group:

• Confirmed CRC patients
• No prior treatment with chemotherapy, radiotherapy, and prior to any surgical procedures

Exclusion Criteria:

• Unwilling to provide stool samples
• FAP (familial adenomatous polyposis), Crohn's disease, ulcerative colitis
• Prior history of colonoscopy within the past 5 years and removal of lesions
• History of CRC
• other conditions deemed not suited for the study by investigators

Subjects with high risk of developing CRC and patients with confirmed CRC