What is your approach for adjuvant therapy when a patient has discordant Oncotype RS (e.g. <20) and MammaPrint (e.g. high risk Luminal B) in node negative HR+Her2- breast cancer?

In terms of the Mammprint, the question here is whether the patient is at low clinical risk or high clinical risk. A stage 1 patient is likely to be considered low clinical risk. In these patients, the MINDACT trial showed that Mammaprint was not able to accurately predict the benefit of chemotherapy.

See the following from the discussion section of MINDACT: "Some 50% of the study patients were defined as being at low clinical risk. In this group, we did not find any meaningful difference in the 5-year rate of survival without distant metastasis between patients at high genomic risk who received chemotherapy and those who did not receive chemotherapy. On the basis of these data, the results for the 70-gene signature do not provide evidence f...

I have started using Mammaprint in low clinical risk patients to identify patients that might be able to safely stop endocrine therapy early (the ultra-low risk patients).
However, I then wonder if it makes sense to also check an Oncotype in case Mammaprint comes back as high risk to find out if there actually is a benefit of chemotherapy.