What causes colon cancer?

Colon cancer: Nobody know for sure. However, recent studies showed genetic mutations in tumor suppressor gene such as apc can be detected in majority of sporadic colon cancer, while dna repair gene mutation account for some high risk colon cancer syndromes known as lynch syndrome. The risk factors include die (fat), alcohol/smoking, prior polyps, ibd, and family history, etc.

Very complicated: Monoclonal theory says that just like we are a living thing, we are born, we have jobs to do and then we die, each cell has a similar cycle of birth, life, and death. Cancer occurs when a cell develops so many mutations that it does not follow that cycle and does not die but can still divide itself and hides from our immune system which is there to detect abnormal cells and destroy them.