Benefits of Neoadjuvant Chemotherapy for Luminal Breast Cancer with Respect to Tumor Response
Received Date : 01 May 2020
Accepted Date : 17 Sep 2020
Available Online : 03 Feb 2021
Doi: 10.37047/jos.2020-75852 - Article's Language: EN
J Oncol Sci. 2021;7(1):7-14
This is an open access article under the CC BY-NC-ND license
Objective: The pathological complete response (PCR) rate following neoadjuvant chemotherapy (NAC) is prognostic for overall survival (OS). We evaluated the pathological responses to NAC and related factors in luminal type HER2-positive breast cancer. Materials and Methods: Hormone receptor (H), HER2/neu status, and Ki67 index were evaluated on 258 core biopsies of breast cancer before NAC. In total, 194 cancer core biopsies were found to be luminal A or B. A Ki67 index of above 20% together with hormone receptor positivity and HER2 negativity further confirmed the breast cancer type as luminal B. The relation between pathological responses and the data obtained were evaluated using the Chi-square test. The OS and disease-free survival (DFS) and related factors were analyzed with univariate analysis. Results: PCR was achieved in 47 (18.2%) patients, and the objective response was 70.2% after NAC. The 5-year DFS rate was 59.2% that related to surgery type; T, N, and postoperative stages; lymphovascular invasion (LVI); perineural invasion (PNI); and pathological response to NAC (p < 0.001). The median OS could not be reached, and the 5-year OS rate was 88.5%. Furthermore, the N and postoperative stages, recurrence, and pathological response to NAC were related to OS. The hormone receptor positivity was related to pathological response (p = 0.03). Although partial and complete responses were high among hormone receptor-negative tumors, the stable response was more common among hormone receptor-positive ones. Conclusions: It should be better to recommend NAC to hormone receptor-negative or HER2-positive tumors unless surgery could not be performed because of the locally advanced tumor due to lower rate of PCR or partial response with NAC in hormone receptor-positive tumors.