Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum (parts of the large intestine).[5] Signs and symptoms may include blood in the stool, a change in bowel movements, weight loss, abdominal pain and fatigue.[9] Most colorectal cancers are due to old age and lifestyle factors, with only a small number of cases due to underlying genetic disorders.

Reference
Wiki: Sigma-rectum tumour