How do you select the triple negative patients from the METABRIC cohort? This is easily done with the TCGA, based of IGC and expression data but not so simple with the info contained within METABRIC.

A number of papers have published analysis based on the triple-negative cohort within the METABRIC cohort:

e.g. Article Triple-Negative Breast Cancer and the Need for New Therapeutic Targets

but none that I have seen state how patients were selected (this is very frustrating, incomplete methods!!). Also the number featured within publications varies greatly, from 300. Does anyone have this information, or the list of triple negative patient IDs?