Clinicopathological Factors and Nomogram Development for Predicting Lymph Node Metastasis in Locally Advanced Rectal
Background:
Research on lymph node metastasis (LNM) in locally advanced rectal cancer (LARC) remains significantly underexplored. This study investigates the clinicopathological factors associated with LNM in LARC and develops a predictive nomogram for clinical application.
Methods:
A retrospective analysis was performed on 1270 patients with LARC who underwent radical surgery between 2018 and 2023. Univariate and multivariate logistic regression analyses were conducted to identify independent predictors of LNM. A nomogram integrating these predictors was constructed and internally validated using bootstrap resampling. Subgroup analyses were carried out to compare stage N1 (n=333) and stage N2 (n=265) patients to determine the risk factors for advanced metastasis.
Results:
The detection rate of LNM was 47.0% (598/1270). Independent risk factors included mucinous adenocarcinoma (OR=1.529, P =0.018), bowel obstruction (OR=1.418, P =0.014), poor tumor differentiation (OR=2.468, P <0.001), perineural invasion (OR=1.784, P =0.003), and lymphovascular invasion (LVI, OR=2.741, P <0.001). Conversely, a history of alcohol consumption (OR=0.721, P =0.016) and microsatellite instability-high (MSI-H) status (OR=0.241, P =0.005) appeared to exert protective effects. The nomogram demonstrated moderate predictive accuracy ( C -index: 0.657, 95% CI: 0.627-0.686). In subgroup analyses, Ki-67 expression emerged as an additional independent risk factor for stage N2 patients (OR=1.016, P =0.040).
Conclusion:
This study elucidated key risk factors for LNM in LARC patients and developed a nomogram for clinical use, offering valuable insights for the design and implementation of multidisciplinary perioperative treatment strategies.
