Accuracy and Influencing Factors of Axillary Lymph Node Ultrasound Assessment After Neoadjuvant Chemotherapy in Breast Cancer

Liang-Qin Peng,1 Xin Tang,2 Guang-Xu Yang,1 Ying Zhu3 1Department of Ultrasound, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, 563000, People’s Republic of China; 2Department of Ultrasound, Longhua District People’s Hospital of Shenzhen, Shenzhen, Guangdong, 518100, People’s Republic of China; 3Department of Ultrasound, Shanghai Ruijin Hospital, Affiliated with the Medical School of Shanghai Jiaotong University, Shanghai, 200025, People’s Republic of ChinaCorrespondence: Ying Zhu, Department of Ultrasound, Shanghai Ruijin Hospital, Affiliated with the Medical School of Shanghai Jiaotong University, No. 197 Ruijin 2nd Road, Huangpu District, Shanghai, 200025, People’s Republic of China, Email [email protected]: Breast cancer is one of the most common malignancies among women worldwide. Neoadjuvant chemotherapy (NAC) has become a standard treatment for locally advanced breast cancer, offering several advantages. However, accurate assessment of axillary lymph node status after NAC is crucial for surgical planning and prognosis. Although the role of ultrasound in axillary staging has been studied, its accuracy in the post-NAC setting remains controversial.Research Gaps: Previous studies have small sample sizes and do not comprehensively analyze factors influencing ultrasound performance. This study aims to evaluate the accuracy of ultrasound in assessing axillary lymph node status after NAC in breast cancer patients and identify clinicopathological factors affecting its performance.Methodology: This retrospective cohort study analyzed data from 171 breast cancer patients who underwent NAC followed by surgery at Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, between January 2015 and December 2019. Ultrasound assessments of axillary lymph nodes were compared with final pathological results. The impact of various clinicopathological factors on ultrasound accuracy was evaluated using univariate and multivariate logistic regression analyses.Results: The overall accuracy of ultrasound in predicting axillary lymph node status after NAC was 76.2%, with a sensitivity of 68.4% and specificity of 83.7%. Factors significantly affecting ultrasound accuracy included tumor size reduction rate, lymph node cortical thickness change, and tumor biological subtype.Conclusion: This study shows that ultrasound has moderate accuracy in assessing axillary lymph node status after NAC, but ultrasound alone is not sufficient for definitive assessment, and surgical confirmation is still necessary. The identified significant factors can optimize the use of ultrasound in post-NAC axillary staging.Keywords: breast cancer, neoadjuvant chemotherapy, axillary lymph nodes, ultrasound, accuracy