HR status defines two different subsets of HER2 positive cancers
 

Human epidermal growth factor (HER2) positive breast cancers are often treated with the same therapy regardless of hormone receptor status. New research published in BioMed Central's open access journal Breast Cancer Research shows that women whose HER2 positive cancer was also hormone (estrogen and progesterone) receptor (HR) negative had an increased risk of early death, and that their cancer was less likely to recur in bone than those whose cancer retained hormone sensitivity.

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