LS is the most common cause of hereditary bowel cancer and people with it also have an increased risk of developing other cancers including womb, ovarian and stomach. Testing for the condition helps to identify whether the patient’s family may also be at increased risk of cancer, meaning they could be monitored more closely if needed.
The guidance recommends that microsatellite instability (MSI) testing or immunohistochemistry (IHC) should be used to detect abnormalities that might mean the presence of LS.
Where these tests show the person has a risk of having LS the guidance recommends further tests are carried out to confirm the diagnosis. Because LS is an inherited condition, a positive test can lead to testing for family members.
Diagnosing LS may also help with the choice of treatments for colorectal cancer; for example, to direct chemotherapy or surgery.
People with LS who develop colorectal cancer generally do so at a younger age usually between the aged of 40-50 or younger.
Expanding testing to all people with colorectal cancer will increase the detection of Lynch syndrome and identify families who could benefit from genetic testing to determine if other family members have Lynch syndrome. This could lead to increased surveillance and consequently improved patient outcomes through earlier diagnosis and treatment,
LS accounts for approximately 3.3% (1 in 30) of colorectal tumours, and the condition is estimated to lead to over 1,100 colorectal cancers a year in the UK.
Professor Carole Longson MBE, director of the centre for health technology assessment at NICE, said: “While these tests have been available for a while the committee heard that there is currently wide variation in the provision of testing for Lynch syndrome and other inherited colorectal cancers; it is estimated by Bowel Cancer UK that only 50% of centres provide tests to assess the risk of Lynch syndrome in people diagnosed with colorectal cancer under the age of 50.
“The committee concluded that using these tests to assess the risk of Lynch syndrome in all patients diagnosed with colorectal cancer could have substantial benefits for patients and their families.”
Deborah Alsina MBE, Chief Executive, Bowel Cancer UK, said: “This final recommendation is a significant development in improving the identification of people with Lynch syndrome – a serious genetic condition that can increase their risk of bowel and other cancers by up to 80%.
“An estimated 175,000 people have Lynch syndrome in the UK but a staggering 95% of those do not know they have it. It’s absolutely vital people who have Lynch syndrome are identified, so they can take steps to reduce their risk of recurrence or for family members, of preventing cancer from developing.
“This is just the first step though. We now need to ensure that hospitals have the resources and a robust process in place to ensure that they can test everyone diagnosed with colorectal cancer and their families and then are able to provide the surveillance screening needed by those affected.”
NICE has also produced an adoption support tool that provides practical information and advice on implementing the guidance. To develop the tool NICE worked with 5 NHS organisations to share their learning and experiences of adopting molecular testing strategies.