The most common form of colon and rectal cancer occurs without a personal or family history. Other types of colon and rectal cancers have a genetic component.

Hereditary Colorectal Cancer

Hereditary colorectal cancer means that the cancer gene is passed down in the family. However, it is unclear which gene causes the disease. If more than one person in a family has colon or rectal cancer, it could mean that the potential for developing this form of cancer has been passed from one generation to the next.

Lynch Syndrome

Also known as hereditary nonpolyposis colorectal cancer (HNPCC), Lynch syndrome was first described more than 100 years ago. (Nonpolyposis means that the cancer can occur with only a small number of polyps present or even with none at all.) It is the most common of the recognized inherited colorectal cancer syndromes.

As an inherited condition, the tendency to develop Lynch syndrome is passed down in the family.