The preoperative prognostic nutrition index is a prognostic indicator for survival in elderly gastric cancer patients after gastrectomy: a propensity score-matched analysis

The incidence of gastric cancer (GC) in elderly patients has increased, and it is important for predicting prognosis for those patients. The prognostic nutrition index (PNI), which is a indicator of nutrition status, is useful for the assessment of prognosis for various cancers. The aim of this propensity score-matched study was to investigate the significance of the PNI for predicting the long-term outcome of GC patients who were 80 years old or older. This study included 127 elderly GC patients who underwent gastrectomy. The optimal cutoff value for the PNI score was defined using a receiver operating curve analysis. For the analysis of long-term outcomes, 86 patients were selected by propensity score matching. The long-term outcomes and prognostic factors after gastrectomy were analyzed by univariate and multivariate Cox regression analyses. The cutoff value for the PNI score was set at 46.5. Among the 86 patients, 30 patients died due to noncancer-related disease. The 5-year cancer-specific survival rates of patients with a PNI score < 46.5 and PNI score >= 46.5 were 73.5% and 84.6%, respectively (P = 0.832). The 5-year overall survival rates of patients with a PNI score < 46.5 and PNI score >= 46.5 were 38.2% and 49.3%, respectively (P = 0.004). According to the multivariate analysis, the PNI score (HR 2.15; 95% CI 1.37-3.94; P = 0.013) and pathological stage (HR 2.16; 95% CI 1.02-4.61; P = 0.045) were independent prognostic factors. The PNI is a promising assessment tool for predicting OS in elderly GC patients.