Objective:

To explore the associations between the prognostic nutritional index (PNI) score, hemoglobin-albumin-lymphocyte-platelet (HALP) score, and lymph node metastasis (LNM) in breast cancer patients, highlighting the significance of these associations for treatment strategies.

Key Findings:

• 51.6% of patients had LNM, with significantly lower median HALP and PNI scores in LNM-positive patients.
• Optimal cutoff values for HALP and PNI were determined to be 39.95 and 52.45, respectively.
• Low PNI levels were significantly associated with LNM (OR: 1.481, 95% CI: 1.016-2.159, p = 0.041), while HALP was not (p = 0.257).

Interpretation:

Low PNI may serve as a risk factor for lymph node metastasis in breast cancer, suggesting its potential use as a clinical warning tool, particularly in preoperative assessments.

Limitations:

• Retrospective design may introduce selection bias and confounding factors.
• Single-center study limits generalizability of findings.

Conclusion:

PNI can be a useful indicator for assessing the risk of LNM in breast cancer patients, highlighting the importance of nutritional and immune interventions, and suggesting areas for future research.