Patients suspected with colorectal cancer who come to our hospital to conduct colonoscopy procedure will be recruited for this study and will undergo a series of examinations.

Asia Pacific Colorectal Screening (APCS) is a validated tool to predict the risk of colorectal cancer in asymptomatic Asian population. The scoring system comprises of three categories: low risk (score 0-1), moderate risk (score 2-3) and high risk (score 4-7). Patients with moderate and high risk will undergo further examinations.

Gut microbiome examination will be conducted with next generation sequencing (NGS) method

Asia Pacific Colorectal Screening (APCS) is a validated tool to predict the risk of colorectal cancer in asymptomatic Asian population. The scoring system comprises of three categories: low risk (score 0-1), moderate risk (score 2-3) and high risk (score 4-7). Patients with moderate and high risk will undergo further examinations

Carcinoembryonic antigen (CEA) is a well-known marker for colorectal cancer. A pre-treatment serum CEA level of ≥ 5 ng/mL is associated with poor prognosis in colorectal cancer patients.

NF-ҡB is a chronic inflammation marker found in colorectal cancer patients. Presence of NF-ҡB is assessed with immunohistochemical method. The result is considered positive if accumulated score ≥ 3.

Fecal immunochemical test (FIT) is a recommended screening method for colorectal cancer. Detection of hemoglobin over a certain level in fecal samples indicated a positive FIT. Patients with positive FIT will undergo further examinations