“…Level IB evidence 7,8 indicates that withholding chemotherapy is associated with a high-risk of recurrence in the high-risk subgroups identified through Oncotype dx 2,9-12 , Prosigna 11,12,[15][16][17][18] , and EndoPredict 22,23 . Although Oncotype dx, Prosigna, and EndoPredict are supported by level IB evidence for prognosticating high risk of recurrence in a subgroup of patients, only Oncotype dx has been evaluated to determine its ability to predict a benefit from chemotherapy.…”