C-reactive protein/albumin ratio as a predictor of survival of metastatic colorectal cancer patients receiving chemotherapy

Preoperative C-reactive protein/albumin (CRP/Alb) ratio has been reported to be an independent prognostic marker in patients with hepatocellular carcinoma. This retrospective study assessed whether CRP/Alb ratio was prognostic in 148 patients newly diagnosed with metastatic colorectal cancer. CRP/Alb ratio was correlated with pre-treatment baseline characteristics. Receiver operating characteristic (ROC) curves assessed survival at 6 and 12 months, with areas under the curve for CRP/Alb compared with those of inflammation-based prognostic scores, including Glasgow Prognostic Score (GPS), modified GPS, neutrophil-to-lymphocyte ratio (NPR), platelet-tolymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR). The optimal CRP/Alb cut-off was 0.6712, with higher CRP/Alb significantly associated with greater age (P = 0.035); higher neutrophil (P < 0.001), platelet (P = 0.016) and monocyte (P = 0.001) counts; higher CRP (P < 0.001); and lower lymphocyte counts (P = 0.038) hemoglobin (P = 0.001) and Alb (P < 0.001). The CRP/Alb ratio had higher AUC values at 6 and 12 months than corresponding GPS, mGPS, NPR, PLR, and MLR. AUCs for CRP/Alb ratio differed significantly from mGPS, NLR, PLR and MLR at 6 and 12 months. Six-month survival rates in patients with CRP/Alb ≤ 0.6712 and > 0.6712 were 91.7% and 44.5%, respectively. These findings, showing that the CRP/Alb ratio is a better predictor of 6 month survival rates than indicators of systemic inflammation, including GPS, mGPS, NLR, PLR, and MLR, in patients with metastatic colorectal cancer, suggest that patients with a higher CRP/Alb ratio may require more aggressive treatment. Prospective multicenter studies are required to confirm the prognostic value of the CRP/Alb ratio.