Example clinical scenario
A 39-year-old woman is diagnosed with a grade 3 ER-positive, PR-positive and HER2 negative breast cancer. There is no evidence of metastatic disease. The patient reports a family history of breast cancer: her mother died of metastatic breast cancer at the age of 42 years. You wish to undertake genomic testing and are considering what constitutional (germline) and/or somatic (tumour) is available and appropriate for her.
When to consider genomic testing
Constitutional (germline) testing
- Women with breast cancer (primary or metastatic) are eligible for constitutional (germline) genomic testing of BRCA1, BRCA2, PALB2, ATM* and CHEK2* genes (*truncating variants only) if they meet at least one of the following criteria:
- triple-negative breast cancer diagnosed <60 years;
- breast cancer (grade 2 or higher) diagnosed <40 years;
- bilateral breast cancer and both cancers diagnosed <50 years;
- breast cancer diagnosed <45 years and a first-degree relative (FDR) with breast cancer <45 years;
- Ashkenazi Jewish ancestry and breast cancer at any age; or
- pathology-adjusted Manchester score ≥15 or CanRisk carrier probability of ≥10%. (These tools can be used to calculate risks. If you are not confident to do so, seek support from your local clinical genetics service.)
- Women diagnosed with breast cancer ≤30 years or patients with triple-positive breast cancer (ER+/PR+/HER2+) ≤35 years of age are also eligible for testing of TP53. Testing can be taken contemporaneously with testing of other genes, after appropriate pre-test counselling.
- Consider referral to genetics for any woman with breast cancer (primary or metastatic) who has a personal and/or family history of endometrial, thyroid, diffuse gastric cancers or non-cancerous features such as cleft lip/palate, macrocephaly, mucocutaneous lesions, or a history of intussusception, which may be features of an underlying syndromic cause of breast cancer predisposition.
- Women with lobular breast cancer may be eligible for CDH1 testing if they meet one of the following criteria:
- lobular breast cancer <70 years and diffuse gastric cancer <70 years;
- lobular breast cancer and ≥FDR/SDR has diffuse gastric cancer (≥1 case occurred <70 years);
- two cases of lobular breast cancer<50 years, such as bilateral or multiple ipsilateral tumours.
Somatic (tumour) testing
- No somatic testing is currently available within the NHS solely on the basis of a positive family history of breast cancer.
- Selected ER-positive, HER2-negative, lymph node-negative breast cancers with an intermediate risk of distant recurrence (using a validated tool such as Predict or the Nottingham Prognostic Index) are eligible for tumour profile testing (for example, Oncotype DX, Prosignia, Endopredict) to inform discussions about adjuvant chemotherapy.
- Other somatic testing for primary breast cancer may be available within clinical trials.
- In the future, somatic testing is likely to be available and expanded to include larger somatic gene panels. Ultimately, paired somatic and constitutional whole genome sequencing will be performed.
What do you need to do?
- Consult the National Genomic Test Directory eligibility criteria to ensure your patient is eligible for testing. You can also refer to this spreadsheet of all available tests.
- For information on the genes that are included on different gene panels for constitutional (germline) testing, see the NHS Genomic Medicine Service signed-off panels resource.
- For germline testing of patients affected with breast cancer, the panel to request is:
- R208: This tests for constitutional (germline) mutations in BRCA1 and BRCA2, PALB2, ATM* and CHEK2* (*truncating variants only).
- Women diagnosed with breast cancer <30 years, or women <35 with triple-positive (ER+,PgR+, HER2+) breast cancer are also eligible for TP53 testing (R216) after appropriate counselling.
- For constitutional DNA-based tests (all the above listed constitutional tests), an EDTA sample is required. Please refer to your local Genomics Laboratory Hub for details of test request forms and where to send samples
- A record of discussion (RoD) form is required prior to constitutional (germline) tests. If you have not completed an RoD form before and/or do not have access to one, please review this Knowledge Hub article on how to complete an RoD form.
- Depending on the details you provide and the test that is chosen, a range of different genomic investigation techniques will be applied to your patient’s/their family’s (if appropriate) DNA. These tests include (but are not restricted to):
- The tumour profile genomic tests detailed above can be requested using the following codes:
- M3.2 Multi-target expression array (Oncotype DX)
- M3.3 Multi-target expression array (Endopredict)
- M3.4 Multi-target expression array (Prosignia)
- These somatic genomic tests are all performed on formalin-fixed tumour samples. Liaise with your local cellular pathology department to confirm local contract and request arrangements.
- Mainstreaming Cancer Genetics: BRCA toolkit
- NHS England: National Genomic Test Directory and eligibility criteria (note that somatic (tumour) tests are listed in the directory for cancer, while constitutional (germline) tests are listed in the directory for rare and inherited disease)
- NICE: Guidance on genetic testing for patients with breast and ovarian cancer
- Breast Cancer Now: ‘Family history of breast cancer: managing your risk’ booklet
- Cancer Research UK: Inherited breast cancer information
- Macmillan: Inherited breast and ovarian cancer information
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