Colon Cancer, The Genetic Factor Colon cancer is the fourth most
common cancer in the United States. In the US an estimated
130,000 men and women will develop colon cancer and more than
50,000 will die from it each year. The life-time risk for
individuals to develop colon cancer is approximately 6%, but the
risk increases to 18% among individuals who have a first degree
relative (parent, sibling or child) with colon cancer. What
causes colon cancer? When genes that normally control cell
multiplication and growth mutate (change), the cells may
multiply and grow without restraint. When cells grow without
restraint inside the colon, a colon polyp develops. If
additional genetic changes occur in that polyp, the polyp can
turn cancerous and invade adjacent tissue and spread to distant
sites. The sequence of events by which polyps form, become
cancerous, invade nearby tissue and spread can and often does
take years. How does one acquire the mutations that cause colon
cancer? Inherited mutations will end up in every