Lynch Syndrome

WHO should read this?

This information is geared toward anyone with a personal or family history of colorectal, endometrial, ovarian or stomach cancer.

WHAT is Lynch syndrome?

Lynch syndrome is a hereditary condition that leads to higher odds of developing specific types of cancers at early ages.

Lynch syndrome occurs when genes that repair accidental errors in our genetic code don’t function correctly. This leads to a build-up of damage in other genes that control cell growth, leading to high risk for cancers at early ages.

Lynch syndrome is sometimes referred to as hereditary non-polyposis colorectal cancer (HNPCC) and is caused by mutations in MLH1, MSH2, MSH6, PMS2 and EpCAM/TACSTD1).

WHEN IS Lynch syndrome suspected?

Lynch syndrome is suspected based on cancers that occur in an individual or family. Cancer risks are highly variable, but the odds of developing colorectal cancer may be up to 80% in some families, and the odds for endometrial (uterine) cancer may be up to 60% in some families. There is an elevated (but smaller) risk for cancers of the ovary, stomach, small intestine, hepatobiliary tract (pancreas, bile ducts, gallbladder and liver), urinary tract (ureter and renal pelvis) prostate, brain and skin.

Families with the highest risk for Lynch syndrome have a clustering of colorectal, endometrial or other Lynch-related cancers in three or more close blood relatives, over two or more generations, with one or more diagnosed before age 50. Lynch syndrome should be considered in any individual or family with two or more colorectal, endometrial or other Lynch syndrome cancers and in individuals with colorectal or endometrial cancer diagnosed before age 50. Increasingly, many pathology departments look for features of Lynch syndrome within colorectal or endometrial cancer tissues that have been surgically removed, prompting to a genetics referral.

WHY IS IT IMPORTANT to know whether you have Lynch syndrome?

Early, regular, careful screening saves lives in families with Lynch syndrome by increasing the likelihood of early detection. Early discovery leads to better chances of cure. Colorectal cancer may be prevented with regular screening and removal of pre-cancerous polyps. Preventive surgeries are an option to prevent cancers that have no reliable early detection method. Guidelines for management of Lynch syndrome depend in part on the specific gene involved and are updated regularly. Management for people with Lynch syndrome should be coordinated through a knowledgeable provider and updated at least annually.

HOW DO I FIND OUT whether my family has Lynch syndrome?

The diagnosis of Lynch syndrome is suspected based on personal or family history and may be confirmed by genetic testing in many cases. If your family has features of Lynch syndrome, or if you are concerned about the cancers that have occurred, request a hereditary cancer risk evaluation. Find a genetic counselor convenient to you at

WHAT IS INCLUDED in a hereditary risk evaluation?

An appointment with a genetic counselor is recommended for people at-risk for Lynch syndrome.

A genetic counselor will:

  • Provide an evaluation based on personal and family medical history;
  • Clarify your personal risk and risk for family members to develop cancers; 
  • Discuss strategies to reduce your cancer risk, including screening/surveillance recommendations based on your specific situation;
  • Establish a diagnosis or determine the likelihood that Lynch syndrome is the cause of the cancers that have occurred;
  • Describe how a genetic diagnosis of Lynch syndrome may affect current or future screening, surgery or treatment decisions;
  • Explain your options regarding genetic testing, including benefits, limitations and possible outcomes;
  • Communicate directly with your care providers to ensure coordinated care;
  • Assist with communication about Lynch syndrome to other family members.


Locate a cancer genetic counselor from Minnesota at or ask your doctor for a referral. Genetic counselors from Minnesota and elsewhere can also be located by using the ‘find a counselor’ feature at