In the last 15 years different multigene tests have been developed to stratify patients with early breast cancer in different risk groups by analysing the activity of various genes.
Should 21 gene recurrence score vs. no testing be used for patients who have hormone receptor positive, HER2-negative, lymph node negative or up to 3 lymph nodes positive invasive breast cancer to guide the use of chemotherapy?
For women with hormone receptor positive, HER2-negative, lymph node negative invasive breast cancer, the ECIBC's Guidelines Development Group (GDG) suggests using the 21 gene recurrence score to guide the use of chemotherapy.
Conditional recommendation for the intervention
Very low certainty of the evidence
The GDG did not consider women with node positive invasive breast cancer to be included in this recommendation.
Women with high clinical risk and low genomic risk (larger tumour diameter and higher grade) may experience larger net desirable consequences and provide a better cost-benefit profile.
Women with low clinical risk and high genomic risk may experience smaller or no net desirable consequences. Indirect evidence from other gene based testing (e.g. 70 gene signature) supports that former conclusion.
Considerations for implementation and policy making
Decreasing cost for the test would support widespread use - price negotiations may be appropriate. Data protection issues may be relevant because the samples are sent out (currently conducted only in the US).
Exploration of subgroups with anticipated larger benefits (risk stratification) or those that will not benefit from using the test for stratification to guide chemotherapy use e.g. women under 50.
High clinical risk refers to those patients with HR-positive and HER-2 negative invasive breast cancer with either:
- G1 and node negative and tumour size 3.1-5 cm
- G1 and 1-3 positive nodes and tumour size 2.1-5 cm
- G2 and node negative and tumour size 2.1-5 cm
- G2 and 1-3 positive nodes and any tumour size
- G3 and node negative and tumour size 2.1-5 cm
- G3 and 1-3 positive nodes and any tumour size.
Low clinical risk refers to those patients with HR-positive and HER2-negative invasive breast cancer with either:
- G1 and node negative and tumour size </= 3cm
- G1 and 1-3 positive nodes and tumour size </= 2cm
- G2 and node negative and tumour size </= 2cm
- G3 and node negative and tumour size </= 1cm.
According to Adjuvant! Online (version 8.0 with HER2 Status) described in detail in the MINDACT trial (Cardoso F., van't Veer L.J., Bogaerts J., Slaets L., Viale G., Delaloge S.et al., 70-Gene Signature as an Aid to Treatment Decisions in Early-Stage Breast Cancer, 2016).