Background: Neo-adjuvant chemotherapy(NAC)may affect hormone receptor(HR)and human epidermal growth factor receptor 2(HER2)status in breast cancer patients. However, the correlation between recurrence rates and this status change remains unclear.
Methods: We evaluated 70 consecutive breast cancer patients receiving NAC with anthracyclines and taxanes, with or without trastuzumab, between January 2005 and May 2012. Pre-treatment core needle biopsy samples and specimens obtained after surgery were tested to determine HR and HER2 status. The relationship between HR and HER2 status changes and recurrence rates was then assessed.
Results: Pathological complete response(pCR)was observed in 13 cases and non-pCR was observed in 57 cases. Of the non-pCR cases, HR-positive status changed to HR-negative status in 6.3% of patients, but a change from negativity to positivity was not observed. HER2-positive status changed to HER2-negative status in 48.0% of patients, and a change from negativity to positivity was observed in 12.5% of cases. The recurrence rate among patients with conversion to a HR-negative status was 0%and that among patients with conversion to a HER2-negative status was 25.0%.
Conclusion: Recurrence rates were not significantly associated with HR and HER2 status conversion after NAC. Future research is warranted to confirm out results.