Mammaprint Profiling Improves Breast Cancer Adjuvant Treatment Decisions Interview with:

Dr. med. Rachel Würstlein</strong> Senior Specialist Clinic and Polyclinic for Obstetrics and Gynecology Klinikum der Ludwig-Maximilians-Universität München • Campus Innenstadt Munich

Dr. Rachel Wuerstlein

Dr. med. Rachel Würstlein
Senior Specialist
Clinic and Polyclinic for Obstetrics and Gynecology
Klinikum der Ludwig-Maximilians-Universität München • Campus Innenstadt
Munich What is the background for this study?

Response: Gene expression profiles provide important information on the risk of recurrence, and subtyping in HR+ HER2- early breast cancer, in addition to conventional clinicopathological factors. The PRIMe study was performed by the West German Study Group (WSG) and prospectively investigated the impact of the gene expression tests MammaPrint, a 70-Gene Breast Cancer Recurrence Assay, and the corresponding 80-Gene Molecular Subtyping Assay, BluePrint, on adjuvant chemotherapy decisions for early-stage breast cancer patients.

To do this, a risk assessment (chemotherapy followed by endocrine therapy, versus endocrine therapy alone) for distant metastasis was performed in 452 patients from 27 study centers using conventional clinicopathological factors such as tumour size and grade first, then compared to the results of the gene expression tests MammaPrint and BluePrint. Doctors and patients then reviewed the results and made a decision on the optimal treatment plan, namely in deciding whether or not patients would benefit from, and should therefore be treated with adjuvant chemotherapy. What are the main findings?

Response: The results showed a 28.4% change in patients’ treatment plans, originally based on clinicopathological factors, as a direct result of the data provided by MammaPrint and BluePrint.

The study also demonstrated >90% adherence rate to the MammaPrint results regarding adjuvant treatment decisions. This shows the high confidence that physicians and patients have in the results of the gene-expression tests, with physicians actively changing their previous treatment plans as a consequence. What should readers take away from your report?

Response: The current clinicopathological approach leaves a significant number of women in an unpleasant situation where they are either under- or over-treated. Indeed, the discordance between conventional clinicopathological assessment and the results of gene expression-based tests like MammaPrint and BluePrint is substantial.

The >90% adherence rate to the MammaPrint results regarding adjuvant treatment decisions demonstrated the confidence of physicians in these gene-expression results and therefore played a significant part in the patient’s decision-making process. The PRIMe study also clearly showed that German physicians welcome those tests and have high confidence in the binary high or low risk results delivered by MammaPrint, helping them to provide the safest and most effective treatment plans for their patients. What recommendations do you have for future research as a result of this study?

Response: Decision-making trials are an important part of clinical research. They demonstrate the impact that the data provided by gene expression-base tests can have in routine clinical practice and highlight the current unmet medical need.

The high degree of adherence to the results, and the significant percentage of physicians and patients who changed their existing treatment plan based on the binary results also shows the confidence that the medical community has in these tests. I would like to see this kind of test expanded into different geographical regions to compare the response of physicians globally to this approach to testing.

The collection of follow-up date from patients from the PRIMe trial over time, in the context of their distant metastasis-free survival, would add further confidence to the decision of whether or not to treat a patient with chemotherapy. Demonstrating that MammaPrint Low Risk patients remain metastasis-free after a period of five years, despite forgoing chemotherapy, would further emphasise the value and benefits of the gene expression-based tests. Is there anything else you would like to add?

Response: Following the publication of the results of the PRIMe study, we continued to follow up the actual therapy received by each patient for six months and are calculating the health economic implications. This is currently being reviewed and will be reported soon, adding an extra dimension to the data. Thank you for your contribution to the community.


Wuerstlein R, et al. Results of multigene assay (MammaPrint®) and molecular subtyping (BluePrint®) substantially impact treatment decision making in early breast cancer: Final analysis of the WSG PRIMe Decision Impact Study. Poster presented at San Antonio Breast Cancer Symposium. December 2016; San Antonio, Texas.

Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.
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Last Updated on February 16, 2017 by Marie Benz MD FAAD