Lynch syndrome testing often missed in womb cancer patients

Patients with womb cancer are not being tested for a genetic condition that increases their chance of developing further cancers, a study has found.

Despite NHS guidance, less than half of those eligible received a blood test for Lynch syndrome, an inherited condition that leaves individuals more susceptible to womb and bowel cancer.

Diagnosis of Lynch syndrome is important as it enables patients to take action to reduce their cancer risk, improving outcomes and reducing NHS costs, experts say.

Lynch syndrome affects one in 300 people, but as little as five per cent are aware they have it.

The condition is caused by genetic variants - small changes in DNA - similar to the BRCA genetic variants that increase breast cancer risk. Those with Lynch syndrome have a 50 per cent chance of developing womb cancer in their lifetime, compared to a general population risk of three per cent.

The National Institute for Health and Care Excellence (NICE) recommends that all patients diagnosed with womb or bowel cancer have tumours tested for markers of Lynch syndrome. If identified, they should be referred for genetic counselling to access support and advice and a simple blood test to confirm the diagnosis.

A University of Edinburgh-led study looked at more than 2500 womb cancer cases across the UK and Ireland between 2022 and 2023.

While 91 per cent of tumors were tested for markers of Lynch syndrome, test results were not routinely communicated to the wider clinical team, meaning follow-up genetic counselling and blood tests were not arranged. Two-thirds of the patients eligible for genetic counselling were referred for appointments.

Those who were referred faced long waiting lists, resulting in high drop-out rates. Only 48 per cent of womb cancer patients who should have had further testing ultimately received a blood test.

Gaps in testing mean that many womb cancer patients with Lynch syndrome go undetected, leaving them at risk of developing bowel cancer. Family members are also left vulnerable to cancer risk, unaware they may have the condition.

Early detection would allow the use of preventative measures to reduce the risk of future cancers, such as taking aspirin and having regular colonoscopies to prevent bowel cancer, or hysterectomies to prevent womb cancer, experts say.

The study is published in the journal BMJ Oncology: doi.org/10.1136/bmjonc-2024-000688 [URL will become active after embargo lifts].

The study was coordinated by the UK Audit and Research Collaborative in Obstetrics and Gynaecology (UK ARCOG) and led by Dr Neil Ryan from the University of Edinburgh.

UK ARCOG is a trainee-led national organization comprising doctors in specialty training in obstetrics and gynecology across the UK. It conducts large-scale audits to identify opportunities to enhance the quality, safety, and equity of care provided to patients.

Despite clear guidance and excellent rates of tumour testing, too many women with Lynch syndrome are still being missed because they're not referred for definitive blood testing in a timely way. This not only denies them the chance to reduce their future cancer risk but also prevents their relatives from being tested and protected. Tumour testing is only cost-effective if it leads to diagnosis - we urgently need to make mainstream testing truly mainstream."

Dr. Neil Ryan, overall study lead and clinical lecturer at the University of Edinburgh's Centre for Reproductive Health