Testing Strategies for Lynch Syndrome in People with Endometrial Cancer

Overview

This specialist Guidelines summary provides NICE recommendations on testing for Lynch syndrome in people with endometrial cancer.

Identifying Lynch syndrome at the point of endometrial cancer diagnosis could prevent other cancers in people with Lynch syndrome (such as colorectal cancer) through increased surveillance and strategies to reduce risk. It could also help to identify relatives with Lynch syndrome, to reduce their risk of Lynch syndrome-associated cancers, or increase early detection of cancer.

This summary is intended for use in a secondary care setting by oncologists. Refer to the full guideline for further information. For a summary of NICE guidance on testing for Lynch syndrome in people with colorectal cancer, see here.

Recommendations

• Offer testing for Lynch syndrome to people who are diagnosed with endometrial cancer. Use immunohistochemistry (IHC) to identify tumours with mismatch repair (MMR) deficiency:
  • If IHC is abnormal with loss of MLH1, or loss of both MLH1 and PMS2 protein expression, do MLH1 promoter hypermethylation testing of tumour DNA. If MLH1 promoter hypermethylation is not detected, offer germline genetic testing to confirm Lynch syndrome
  • If IHC is abnormal with loss of MSH2, MSH6 or isolated PMS2 protein expression, offer germline genetic testing to confirm Lynch syndrome
• Healthcare professionals should inform people about the possible implications of test results for both themselves and their relatives, and give support and information. Discussion of genetic testing and obtaining consent should be done by a healthcare professional with appropriate training
• Laboratories doing IHC for MMR proteins, MLH1 promoter hypermethylation testing or germline genetic testing should take part in a recognised external quality assurance programme.