# Systemic Inflammation and Survival in Stage IV Colorectal Cancer: A Retrospective Cohort Study

## TL;DR

This study found that inflammation markers like dNLR are linked to survival in stage IV colorectal cancer but lose significance after adjusting for treatment factors.

## Contribution

The study evaluates the independent prognostic value of dNLR and other lab markers in mCRC after multivariable adjustment.

## Key findings

- In univariable analysis, dNLR tertiles and AST elevation were associated with overall survival.
- After multivariable adjustment, only irinotecan-based therapy remained independently linked to poorer survival.
- Inflammatory markers like dNLR did not retain independent prognostic significance after adjustment.

## Abstract

Background: In metastatic colorectal cancer (mCRC), systemic inflammation and routine laboratory parameters may reflect host–tumor interactions and provide additional prognostic information. This study evaluated the association between baseline clinicopathological and laboratory parameters, including the derived neutrophil-to-lymphocyte ratio (dNLR), and overall survival (OS) in patients with stage IV colorectal adenocarcinoma. Methods: We conducted a retrospective cohort study including 92 patients diagnosed with metastatic colorectal adenocarcinoma and treated at a single oncology center between February 2022 and December 2024. Baseline laboratory parameters were collected at diagnosis. Survival was analyzed using Kaplan–Meier estimates with log-rank testing. Prognostic associations were evaluated using univariable and multivariable Cox proportional hazards regression models adjusted for relevant clinical and treatment-related factors. Results: The cohort was predominantly male (62%) and younger than 70 years (66%), with 80 deaths recorded during follow-up. In univariable analyses, primary tumor resection, irinotecan-based first-line therapy, elevated AST, and dNLR tertiles were associated with OS. However, after multivariable adjustment, only irinotecan-based first-line therapy remained independently associated with poorer survival (HR 2.10, 95% CI 1.16–3.81; p = 0.022). Continuous dNLR, anemia (WHO sex-specific), and AST elevation did not retain independent prognostic significance. Conclusions: In this cohort of patients with mCRC, inflammation-related laboratory markers demonstrated associations with survival in unadjusted analyses but did not remain independent predictors after adjustment for clinical and treatment-related confounders. These findings highlight the importance of rigorous multivariable modeling when evaluating inflammatory biomarkers in metastatic colorectal cancer.