Prognostic role of a new index (multi inflammatory index) in patients with metastatic colorectal cancer: results from the randomized ITACa trial

Aims: We created a new index (Multi Inflammatory Index, MII) composed of an inflammatory index [neutrophil-to lymphocyte-ratio (NLR): MII-1; platelet-to-lymphocyte ratio (PLR): MII-2; or systemic immune-inflammation index (SII): MII-3] and C-reactive protein (CRP). Our aim was to evaluate the prognostic and/or predictive capacity of the MII in the randomized ITACa (Italian Trial in Advanced Colorectal Cancer) study on patients with metastatic colorectal cancer undergoing first-line chemotherapy. Methods: Between November 2007 and March 2012, baseline NLR, PLR; SII and CRP were available for 131 patients, 66 receiving chemotherapy plus bevacizumab and 65 receiving chemotherapy alone. Results: Patients with low (<25) MII-1 levels had a better outcome than those with high (> 25) levels: median progression-free survival (PFS) was 12.4versus8.9 months [hazard ratio (HR) = 1.74, 95% confidence interval (CI) 1.21-2.51,p = 0.003] and median overall survival (OS) was 30.9 monthsversus15.0 months (HR = 2.05, 95% CI 1.40-3.02,p = 0.0002), respectively. Similar results were obtained for patients with low (<1424) MII-2 levels compared with those with high (> 1424) levels: median PFS was 12.6versus8.9 months (HR = 1.95, 95% CI 1.35-2.82,p = 0.0004) and median OS was 32.4versus14.6 months, respectively (HR = 2.42, 95% CI 1.64-3.57,p < 0.0001). Patients with low (<6068) MII-3 levels had a longer median PFS and OS than those with high (> 6068) levels: 12.6versus8.9 months (HR = 1.91, 95% CI 1.33-2.76,p = 0.005) and 30.9versus15.0 months (HR = 2.10, 95% CI 1.43-3.09,p = 0.0002), respectively. Following adjustment for clinical covariates, multivariate analysis confirmed all MII indexes as independent prognostic factors for predicting PFS and OS. Conclusion: All MII indexes appear to be useful as prognostic markers.