The monocyte to red blood cell count ratio is a strong predictor of postoperative survival in colorectal cancer patients: The Fujian prospective investigation of cancer (FIESTA) study

Background and Aims: We sought to evaluate the prognosis of preoperative blood routine parameters for the mortality of colorectal cancer patients after surgery by eliciting a subset of data from the ongoing Fujian prospective investigation of cancer (FIESTA) study. Methods: 1318 colorectal cancer patients with completed survival data were enrolled between 2000 and 2008. Effect-size estimates are expressed as hazard ratio (HR) and 95% confidence interval (CI). Results: The median follow-up time was 58.6 months. Elevated levels of neutrophil (adjusted HR, 95% CI, P: 1.22, 1.06-1.41, 0.006) and monocyte (1.32, 1.06-1.65, 0.013) were significantly associated with an increased risk of colorectal cancer mortality, whereas that of lymphocyte (0.60, 0.44-0.82, 0.001) and red blood cell count (0.20, 0.09-0.43, <0.001) were significantly associated with a reduced risk. Additionally, remarkable significance was reached for the neutrophil-to-lymphocyte ratio (1.12, 1.06-1.19, <0.001) and lymphocyte-to-monocyte ratio (0.60, 0.46-0.79, <0.001). Based on individual effect-estimates, a new derivate, monocyte to red blood cell count ratio namely MRR was created, and its association with colorectal cancer mortality was strikingly significant (1.48, 1.18-1.85, 0.001). Notably, elevated MRR was significantly associated with the mortality of early stage colorectal cancer, especially in patients with stage I-II (1.63, 1.04-2.56, 0.034), invasion depth T1-T2 (2.85, 1.45-5.61, 0.002), regional lymph node metastasis N0 (1.89, 1.29-2.77, 0.001) and tumor size ≤ 4.5 cm (1.84, 1.25-2.70, 0.002). Conclusions: We created a new derivate MRR, which was superior over classic blood routine derivates, and importantly the MRR exhibited a stronger ability in predicting poor prognosis of colorectal cancer, especially at the early stage.