According to the World Health Organization’s data in 2020, colorectal cancer is the third most common cancer after breast cancer and lung cancer, and is ranked second in cancer-related deaths after lung cancer. Approximately 1.9 million people were diagnosed and more than 900,000 patients died of colorectal cancer worldwide. The most common regions with the highest incidence and mortality rates include Europe, Australia, New Zealand, North America, and Eastern Asia.
Once diagnosed at an early stage, colorectal cancer has an impressive survival rate of over 90% at 5 years. However, when it is detected at a late stage that the tumor has spread to other parts of the body, the survival rate is significantly diminished to 14% at 5 years. In 2021, the United States Preventive Services Task Force has lowered the starting age for screening from 50 years old to 45 years old. Among screening tests, colonoscopy is a unique tool that can be used for screening and treatment at the same time if there are any polyps, premalignant, or early malignant lesions detected.