Abstract
BACKGROUND: Previous studies have confirmed that the higher axillary lymph node metastasis rate, the worse the prognosis. This study aimed to determine the key factors associated with axillary lymph node metastasis and prognosis of T2 breast cancer, which ultimately provides a scientific basis for precise risk stratification, optimized treatment decision-making, and improved prognosis in T2 patients. METHODS: Multivariate logistic regression was used to explore the influencing factors of axillary lymph node metastasis in patients with T2 breast cancer. Univariate and multivariate Cox regression were used to explore the prognostic factors of T2 breast cancer patients, and the nomogram was used to predict the survival probability of patients. Kaplan-Meier survival curve was used to analyze the influence of influencing factors on survival. RESULTS: A total of 150,730 patients with T2 breast cancer were included in this study. Age ≥65 years old, and other races were protective factors for axillary lymph node metastasis, while black race, infiltrating cancer, estrogen receptor (ER)-positive, progesterone receptor (PR)-positive, luminal B subtype, human epidermal growth factor receptor-2 (HER2)-positive subtype, and triple-negative subtype were risk factors. Other race, married, right primary site, chemotherapy, ER-positive, PR-positive, HER2-positive subtype, and triple-negative subtype were protective factors for overall survival (OS) of patients with T2 breast cancer, while age ≥65 years old, black race, other marital status, stage II, stage III, axillary lymph node metastasis, and luminal B subtype were risk factors for OS of patients with T2 breast cancer. The same results were also found in the breast cancer-specific survival (BCSS) of patients with T2 breast cancer. The nomogram constructed based on these factors affecting OS and BCSS can be used as a tool to predict OS and BCSS for T2 breast cancer. CONCLUSIONS: Black race, infiltrating cancer, ER-positive, PR-positive, luminal B subtype, HER2-positive subtype, and triple-negative subtype were independent risk factors for axillary lymph node metastasis. Old age, black race, other marital status, stage II, stage III, axillary lymph node metastasis, and luminal B subtype were risk factors for the prognosis of patients with T2 breast cancer.