ASO Author Reflections: Neutrophil-to-Lymphocyte Ratio Predicts Recurrence Pattern in Patients with Resectable Colorectal Liver Metastases

Background Studies have suggested that neutrophil-to-lymphocyte ratio (NLR) has value as a predictor of long-term outcomes in various cancer types. Its prognostic potential in patients with CRLM has not been thoroughly investigated. This original, retrospective study assessed the relationship between the preoperative NLR, survival outcomes, and recurrence patterns in patients after colorectal liver metastasis resection (CRLM). Methods The prospectively maintained database of a tertiary medical center was queried for all patients who underwent CRLM resection between 2005 and 2017. Patients were divided into two groups: NLR <3 (normal) or >3 (high). Recurrence risk was analysed using Fine and Gray correction for competing risk method and cause specific analyses. Results The cohort included 231 patients of whom 53 (23%) had a high neutrophil-to-lymphocyte ratio. At presentation, 35% had synchronous disease and 48% had a solitary metastasis; median tumor size was 2 cm. Patients with a high NLR had a significantly higher rate of simultaneous colorectal resection ( P = 0.01). A high NLR was independently associated with worse OS ( P = 0.02), worse DFS ( P = 0.03), and higher risk of recurrence ( P = 0.048), specifically recurrence with an extrahepatic pattern ( P = 0.03). Conclusions A high preoperative NLR was independently associated with poorer survival outcomes and extrahepatic recurrence pattern. The NLR appears to have prognostic importance in CRLM and may serve as a surrogate marker of aggressive systemic disease after resection. These findings warrant external validation, preferably in a prospective design.