Who is at risk for LS?

All individuals have a chance of developing cancer throughout their lifetime. Colorectal cancer (CRC) refers to cancer that starts in either the colon or the rectum. CRC is very common in Canada. The chance of developing colorectal cancer in the general population is about 1 in 16, or 6%. The average age of diagnosis of CRC in Canada is approximately 65 years.

As we age, the cells that line the colon and rectum are damaged by environmental factors, such as diet and as a normal part of the aging process. Over a lifetime this damage accumulates and can lead to colorectal cancer. This is thought to explain the majority of cases of CRC, which we call sporadic.

We see differences between families with sporadic cases of CRC and families with LS. LS families often have multiple individuals with CRC and other LS-related cancers (i.e. endometrial cancer), several generations with these cancers and the cancers are often diagnosed at younger ages (typically under age 50).