In December 2024 NICE published its recommendations for the use of elacestrant in the treatment of breast cancer.  Elacestrant became available via the Cancer Drugs Fund (CDF) from 19th December 2024 in line with these recommendations.

The guidance stated:

“Elacestrant is recommended as an option for treating oestrogen receptor (ER)-positive HER2-negative locally advanced or metastatic breast cancer with an activating ESR1 mutation that has progressed after at least 1 line of endocrine therapy plus a cyclindependent kinase (CDK) 4 and 6 inhibitor if the cancer has progressed after at least 12 months of endocrine treatment plus a CDK 4 and 6 inhibitor.”

The license for elacestrant requires identification of ESR1 variants from plasma only. Tumour tissue testing is not included in the current license. Testing for ESR1 variants in breast cancer therefore requires the genomic test to be performed on circulating tumour DNA (ctDNA) derived from a blood sample rather than a tissue sample.

ESR1 genomic test information

Testing will be available through the NHS Genomic Medicine Service (NHS GMS). The National Genomic Test Directory has been updated from today, 20th January 2025 to include ctDNA testing for ESR1. The unique genetic test directory code is M3.13.

Testing for ESR1 variants will initially be available through two Genomic Laboratory Hubs (GLH), North Thames (Royal Marsden Hospital) and the North West (Manchester University Hospital) as the designated genomic laboratory providers within the NHS GMS.

This is an interim arrangement until 31st March 2025. The future GLH provider hubs who will deliver the service from 1st April 2025 will be confirmed in due course.

Clinical teams who would normally send patient samples to the regional GLH hub for genetic testing, should send samples for ESR1 ctDNA testing directly to the designated GLH hub provider for their GMS region as described below.

Clinicians in the following GMS geographies are required to refer samples to the North Thames GLH:

• North Thames
• East
• South East
• South West

All other GMS regions should send samples to the North West GLH, further information can be found here information about ESR1 testing on their website.

Testing blood kits can be requested directly from each GLH hub.  Please note, blood kits are specific to the testing technology method used by the two designated GLHs. Therefore, please ensure that the correct blood kit is used for the identified test routing for your GMS region.

Testing specifics for the North Thames GLH

To access blood kits, test request documentation, and for any other information about ESR1 ctDNA testing for the North Thames GLH, please visit the Marsden360 website or email Marsden360@rmh.nhs.uk 

Education and resources

To support the new testing pathway, an education and training webinar was delivered on the 16th January for GMS regions required to route samples to the North Thames GLH hub. A recording of that webinar can be found on our website.