AUTHOR=Ren Xiaoqiu , Yu Yaner , Liu Lihong , Xia Wenjie , Ni Runliang , Wei Shumei , Wu Jun , Wei Qichun 

TITLE=Axillary response and outcome in breast cancer patients after neoadjuvant treatment: The role of radiotherapy in reducing recurrence in ypN0 patients with initially cN+ stage

JOURNAL=Frontiers in Oncology

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2023.1093155

DOI=10.3389/fonc.2023.1093155

ISSN=2234-943X

ABSTRACT=<sec><title>Objective</title><p>We aim to explore the clinicopathological features associated with axillary node response and recurrence in breast cancer patients undergoing neoadjuvant treatment (NAT).</p></sec><sec><title>Methods</title><p>We retrospectively reviewed the medical records of 486 stage I to III breast cancer patients who received NAT and surgery between 2016 and 2021.</p></sec><sec><title>Results</title><p>A total of 486 cases were reviewed and 154 (31.7%) patients achieved breast pathological complete response (pCR) (ypT0/Tis). Of the 366 cases with initially cN+, 177 (48.4%) cases reach ypN0. Breast pCR is in high accordance to axillary pCR (81.5%). Hormone receptor (HR)-/HER2+ breast cancer patients have the highest axillary pCR rate (78.3%). Patients achieve axillary pCR have a significantly better disease-free survival (DFS) (P=0.0004). Further analysis reveals that the DFS of ypN0 and ypN1 cases are similar (<italic>P</italic>=0.9049). Moreover, DFS in patients with ypN0 (<italic>P</italic>&lt;0.0001) and ypN1 (<italic>P</italic>&lt;0.0001) is significantly better than that in patients with ypN2-3. For post-mastectomy ypN0 cases, radiation could only improve DFS in patients with initially cN+ stage (<italic>P</italic>=0.0499). Multivariate Cox regression analysis shows that radiation is an independent factor to improve DFS (Hazard ratio (HR): 0.288(0.098-0.841), <italic>P</italic>=0.0230). Radiation does not improve DFS in pre-cN0/ypN0 patients (<italic>P</italic>=0.1696).</p></sec><sec><title>Conclusion</title><p>Axillary pCR rate is higher than breast pCR rate. HR-/HER2+ patients have the highest axillary pCR rate. Axillary pCR is associated with better DFS. Radiation could further improve DFS in ypN0 patients with initially positive nodal disease.</p></sec>