Prognostic value of preoperative inflammatory response biomarkers in patients with esophageal cancer who undergo a curative thoracoscopic esophagectomy

Background
Several inflammatory response biomarkers, including lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) have been reported to predict survival in various cancers. The aim of this study is to evaluate the clinical value of these biomarkers in patients undergoing curative resection for esophageal cancer.

Methods
The LMR, NLR and PLR were calculated in 147 consecutive patients who underwent esophagectomy between January 2006 and February 2015. We examined the prognostic significance of the LMR, NLR, and PLR in both elderly and non-elderly patients. We evaluated the cancer-specific survival (CSS), with the cause of death determined from the case notes or computerized records.

Results
Univariate analyses demonstrated that TNM pStage (p < 0.0001), tumor size (p = 0.0014), operation time (p = 0.0209), low LMR (p = 0.0008), and high PLR (p = 0.0232) were significant risk factors for poor prognosis. Meanwhile, TNM pStage (p < 0.0001) and low LMR (p = 0.0129) were found to be independently associated with poor prognosis via multivariate analysis.

In non-elderly patients, univariate analyses demonstrated that TNM pStage (p < 0.0001), tumor size (p = 0.0001), operation time (p = 0.0374), LMR (p < 0.0001), and PLR (p = 0.0189) were significantly associated with a poorer prognosis. Multivariate analysis demonstrated that TNM pStage (p = 0.001) and LMR (p = 0.0007) were independent risk factors for a poorer prognosis.

In elderly patients, univariate analysis demonstrated that that TNM pStage (p = 0.0023) was the only significant risk factor for a poor prognosis.

Conclusions
LMR was associated with cancer-specific survival (CSS) of esophageal cancer patients after curative esophagectomy. In particular, a low LMR was a significant and independent predictor of poor survival in non-elderly patients. The LMR was convenient, cost effective, and readily available, and could thus act as markers of survival in esophageal cancer.