Colorectal cancer (CRC) is a malignancy of the large intestine (colon) and/or rectum. It usually begins as small, noncancerous (benign) clumps of cells called polyps that form on the inside of the colon. Hereditary colon cancer syndromes are generally divided into two types, Lynch syndrome and polyposis syndromes. Lynch syndrome, also called hereditary non-polyposis colon cancer (HNPCC), is caused by pathogenic variants in MLH1, MSH2, MSH6, PMS2 and EPCAM. This condition is the most common inherited cause of colorectal cancer. Polyposis syndromes are characterized by the development of numerous precancerous polyps, which may become malignant. There are many treatments available including surgery, radiotherapy, chemotherapy, targeted therapy, and immunotherapy.

      Adults aged 45-75 years old are recommended to be screened for colorectal cancer. People with increased risk such as having family history of colorectal cancer should consider screening sooner.