The preoperative lymphocyte to monocyte ratio predicts clinical outcome in patients with stage III colon cancer.

BACKGROUND: Inflammation has a critical role in the pathogenesis and progression of cancer. The lymphocyte to monocyte ratio (LMR) could be shown to be prognostic in haematologic neoplasia. In this study, we analysed the LMR with clinical outcome in stage II and III colon cancer patients.

METHODS: Three hundred and seventy-two patients with stage II and III colon cancer were included in this retrospective study. Kaplan-Meier curves and multivariate Cox-regression analyses were calculated for time to recurrence (TTR) and overall survival (OS).

RESULTS: Including all patients, the elevated preoperative LMR was significantly associated with increased TTR and OS in multivariate analysis (HR: 0.47, 95%CI: 0.29-0.76, P=0.002; HR: 0.51, 95%CI: 0.31-0.83, P=0.007; respectively). In subanalyses, the association was limited to patients with stage III (HR: 0.40, 95%CI: 0.22-0.72, P=0.002), in contrast to patients with stage II (HR: 0.40, 95%CI: 0.28-1.66, P=0.397). When the subgroup of patients with 'high-risk' LMR≤2.83 was analysed, no benefit of adjuvant 5-FU-based chemotherapy could be found (HR: 0.99; 95%CI: 0.60-1.63; P=0.953).

CONCLUSION: The LMR might be an independent prognostic marker for TTR in stage III colon cancer patients. Our results further suggest that high-risk patients based on the LMR do not benefit from adjuvant chemotherapy. Independent validation of our findings is warranted.