Objective:

To evaluate the prognostic role of the prognostic immune and nutritional index (PINI) specifically in esophageal squamous cell carcinoma (ESCC) patients undergoing neoadjuvant immunochemotherapy (NICT).

Key Findings:

• Optimal PINI cutoff established at 3.320, stratifying patients into low (n=97) and high (n=96) cohorts.
• Low PINI cohort had significantly worse 3-year disease-free survival (DFS) and overall survival (OS) compared to high PINI cohort both before (DFS: 43.3% vs. 76.0%, P<0.001; OS: 58.8% vs. 84.4%, P<0.001) and after (DFS: 48.4% vs. 68.8%, P = 0.021; OS: 64.1% vs. 81.2%, P = 0.033) PSM.
• PINI was confirmed as an independent prognostic index for DFS (HR = 0.423, 95% CI = 0.257-0.696, P = 0.001) and OS (HR = 0.461, 95% CI = 0.250-0.848, P = 0.013) in the pre-matched cohort, and for DFS (HR = 0.543, 95% CI = 0.309-0.955, P = 0.034) in the matched cohort.

Interpretation:

PINI serves as a significant independent prognostic factor, particularly for disease-free survival, in ESCC patients receiving NICT, suggesting its potential utility in clinical risk stratification and personalized treatment approaches.

Limitations:

• Retrospective design may introduce selection bias.
• Single-center study limits generalizability of findings and may affect the robustness of the conclusions.

Conclusion:

Incorporating PINI into existing prognostic models may enhance long-term risk stratification and assist in personalizing therapeutic strategies for ESCC patients undergoing NICT.