Received: 4 May 2017
Accepted: 9 January 2018
First Online: 30 January 2018
Ethics approval and consent to participate
: This study makes use of data generated by TCGA Research Network (ExternalRef removed) and the Molecular Taxonomy of Breast Cancer International Consortium (Metabric). Funding for the Metabric project was provided by Cancer Research UK and the British Columbia Cancer Agency Branch.
: Not applicable.
: All authors are employees of Genentech and hold shares in Roche.
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