To identify independent predictors of metastasis in ARM lymph nodes and to develop and validate a preoperative nomogram for predicting the risk of metastasis in breast cancer patients.
Approach:
Patient Cohorts: A retrospective analysis was conducted on a development cohort of 142 breast cancer patients and an independent validation cohort of 54 patients.
Mapping Technique: Indocyanine green and methylene blue were used to map lymphatic drainage during surgery.
Statistical Analysis: Univariable and multivariable logistic regression analyses were performed to identify independent predictors of metastasis.
Nomogram Development: A preoperative nomogram was developed and validated based on identified predictors.
Key Findings:
ARM lymph nodes were identified in 92.81% of patients, with a metastasis rate of 23.24%.
Independent predictors of metastasis included menarche age ≤ 12 years, elevated fibrinogen, elevated CA15-3, elevated platelet-to-lymphocyte ratio, presence of sentinel ARM lymph nodes, larger ARM lymph node long diameter, and ultrasound-detected axillary abnormalities.
The nomogram showed excellent discrimination in the development cohort (AUC = 0.934) and acceptable discrimination in the validation cohort (AUC = 0.826).
Interpretation:
The developed nomogram predicts the risk of ARM lymph node metastasis.
Limitations:
The study is retrospective and may have inherent biases.
The sample size for the validation cohort was relatively small.
Conclusion:
The preoperative nomogram supports selective ARM node preservation.
