The Lymphocyte to Monocyte Ratio in Peripheral Blood Represents a Novel Prognostic Marker in Patients with Pancreatic Cancer

Background: Intra-tumoral macrophages have been involved as important players in the pathogenesis and progression of cancer. Recently, inflammatory parameters of the systemic inflammatory response have also been proposed as usefully prognostic biomarkers. One of these, the lymphocyte to monocyte ratio (LMR) in peripheral blood has been shown as a prognostic factor in hematologic and some solid tumors. In this study we analyzed for the first time the prognostic value of LMR in a large middle European cohort of pancreatic cancer (PC) patients.

Methods: Data from 474 consecutive patients with ductal adenocarcinoma of the pancreas were evaluated retrospectively. Cancer-specific survival (CSS) was analyzed using the Kaplan-Meier method. To further evaluate the prognostic significance of the LMR, univariate and multivariate Cox regression models were calculated.

Results: Increased LMR at diagnosis was significantly associated with well-established prognostic factors, including high tumor stage and tumor grade (p<0.05). In univariate analysis, we observed that an increased LMR was a significant factor for better CSS in PC patients (HR 0.70; 95% CI 0.57-0.85; p<0.001). In multivariate analysis including age, Karnofsky Index, tumor grade, tumor stage, administration of chemotherapy, LMR and surgical resection, we confirmed increased LMR as an independent prognostic factor for CSS (HR 0.81; 95% CI 0.66-0.99; p=0.04).

Conclusions: In conclusion, we identified LMR as an independent prognostic factor in PC patients. Our results indicate that the LMR might represent a novel and useful marker for patient stratification in PC management.