A new study published in the journal Breast Cancer Research reveals that the risk of early death among women who are diagnosed with human epidermal growth factor (HER2) positive breast cancers, and whose hormone receptors (HR) are also negative, was high and added that the cancer was less likely to recur in bone compared to those whose cancer retained hormone sensitivity.
Breast cancer is a heterogeneous disease with many different subtypes. HR positive cancer is more likely to be luminal A or B type and be treated with endocrine therapy including tamoxifen or aromatase inhibitors, while HR negative cancer is more likely to be basal or 'HER2-enriched'. HER2 positive cancers can fall into both of these categories.
A multicentre study from 13 National Comprehensive Cancer Network (NCCN) hospitals analysed data from over 3000 women diagnosed with early stage HER2 positive breast cancer. At first recurrence, most of the women in the study were treated with chemotherapy and/or with anti-HER2 therapy.
Dr Vaz-Luis, continued, "Based on our findings, HR status defines two different subsets of HER2 positive cancers. To combat this, we believe that studies which look at new drugs for treating HER2-positive breast cancer should also integrate hormone receptor status into their design."