Inflammatory biomarkers in metastatic colorectal cancer: prognostic and predictive role beyond the first line setting

Introduction Inflammatory biomarkers are useful prognostic tools in cancer patients. However, the prognostic and predictive value of inflammatory biomarkers beyond the 1st-line setting in metastatic colorectal cancer (mCRC) is unclear. Results In multivariate analysis 1 standard deviation increase in neutrophil-lymphocyte-ratio (NLR) was associated with an 8.5% absolute lower objective-response-rate (ORR) in 1st-line (p<0.0001), 3% lower ORR in 2nd-line (p< 0.0001), and 3% lower ORR in 3rd-line (p=0.24), respectively. Regarding progression free survival (PFS), an increase in the NLR was significantly associated with rising hazard-ratios (HR) over all treatment lines (HR=1.30, p= 0.021 1st-line); (HR=1.37, p<0.0001 2nd-line); (HR=1.44, p=0.042 3rd-line). The platelet-lymphocyte-ratio (PLR) was associated with 6-month PFS over all three treatment lines. Higher C-reactive-protein (CRP) predicted for worse PFS in the first two chemotherapy lines and in best supportive care (BSC). (HR=1.49 (p<0.0001 1st-line); HR=1.25 (p=0.007 2nd-line); HR=1.09 (95%CI 0.81-1.48, p=0.552 3rd-line and HR=1.43 (p= 0.002 in BSC)). Methods Two-hundred-fifty-eight patients with mCRC undergoing palliative chemo(immuno-)therapy were retrospectively included. Primary endpoints were 6-month PFS and ORR during 1st-line, 2nd-line, and 3rd-line treatment, and 6-month overall survival during BSC. Conclusion This study shows that inflammatory biomarkers are useful predictors of disease outcome and treatment response over several treatment lines in mCRC patients.