Improving the effectiveness of neoadjuvant chemotherapy in patients with breast cancer with positive estrogen receptor (HR) and HER2 negative.

e12120Background: The effect of pathologic complete response (pCR) after neoadjuvant chemotherapy is considered independent of the breast cancer subtype, but the pCR rate in HR positive/HER2 negative patients is smaller than other subtype so it is interpreted as pCR is not being prognostic in luminal breast cancer. In large series residual cancer burden (RCB) assessed by Symmans methods is prognostic in luminal patients if RCB-0 and RCB-I are combined. Methods: 166 patients (March 2000-august 2016) with neoadjuvant chemotherapy based treatment were retrospectively analysed in order to find if common clinicopathological factors could select patients with significative better response considered as pCR or RCB type 0 and I. Results: Median age was 53 years (29-82), median tumor size of 41 mm and 54% of tumors had initial nodal involvement. All patients were estrogen positive and 45% progesterone receptor negative with a median of ki67 expression of 32%. A total of 10% pCR rate was found and the response type...