Lymph node ratio predicts adjuvant chemotherapy benefit in esophageal squamous cell carcinoma.

Background: The lymph node ratio (LNR) has emerged as an important prognostic factor in various cancers, including esophageal squamous cell carcinoma (ESCC). This study aimed to evaluate the utility of LNR in guiding decisions for adjuvant chemotherapy in ESCC patients following resection.

Materials and methods: A retrospective analysis was conducted on 2267 patients who underwent potentially curative surgery for ESCC at Sichuan Cancer Hospital and Institute between January 2010 and December 2017. Univariate and multivariate Cox proportional hazards regressions were used to assess factors influencing overall survival (OS), with LNR analyzed using restricted cubic splines (RCS) to explore its relationship with treatment and survival outcomes. Propensity score matching (PSM) was employed to adjust for biases between treatment groups.

Results: Among the patients, 1416 underwent surgery alone (S group) and 851 received surgery plus adjuvant chemotherapy (S + CT group). The median LNR was 3%, with an interquartile range of 0%-12%. RCS analysis identified an LNR threshold of 11%, below which patients showed a significant OS benefit from adjuvant chemotherapy (hazard ratio [HR]: 0.57; 95% CI: 0.46-0.71; P < 0.001). However, patients with an LNR above 11% did not derive any OS benefit from chemotherapy (HR: 0.87; 95% CI: 0.70-1.09; P = 0.238).

Conclusion: These findings suggest that LNR is a valuable marker for identifying ESCC patients who would benefit from postoperative adjuvant chemotherapy. A threshold LNR of 11% can help personalize treatment strategies, and patients with higher LNRs may require more intensive approaches like chemoradiotherapy to improve survival. Further prospective studies are needed to validate these results.