Introduction: Current risk stratification tools for patients with colorectal cancer (CRC) rely on final surgical pathology but may be improved with the addition of novel serum biomarkers. The objective of this study was to evaluate the utility of preoperative NLR and PLR in predicting long-term oncologic outcomes in patients with operable CRC.
Methods: All patients who underwent curative resection for adenocarcinoma at a large tertiary academic hospital were identified. High NLR/PLR was evaluated preoperatively and defined by maximizing log-rank statistics. Recurrence-free survival (RFS) and overall survival (OS) were calculated using the Kaplan-Meier method and compared by the log-rank test. Univariate and multivariable Cox proportional hazard regression was used to identify associations with outcome measures.
Results: A total of 549 patients were included in the study. High NLR (≥2.6) was associated with worse RFS (hazard ratio [HR] 2.03, 95 % confidence interval [CI] 1.48-2.79, p < 0.001) and OS (HR 2.25, 95 % CI 1.54-3.29, p < 0.001). High PLR (≥295) also was associated with worse RFS (HR 1.68, 95 % CI 1.06-2.65, p = 0.028) and OS (HR 1.81, 95 % CI 1.06-3.06, p = 0.028). In the multivariable model, high NLR retained significance for reduced RFS (HR 1.59, 95 % CI 1.1-2.28, p = 0.013) and OS (HR 1.91, 95 % CI 1.26-2.9, p = 0.002). Significantly more patients in the high NLR group were older at diagnosis, had mucinous adenocarcinoma, higher T stage, and advanced cancer stage.
Conclusions: High preoperative NLR in this series was shown to be a negative independent prognostic factor in patients undergoing surgical resection for nonmetastatic CRC. The prognostic utility of this serum biomarker may help to guide use of adjuvant therapies and patient counselling.