Published online May 21, 2015. doi: 10.3748/wjg.v21.i19.5961
Peer-review started: October 20, 2014
First decision: December 26, 2014
Revised: January 9, 2014
Accepted: January 21, 2015
Article in press: January 21, 2015
Published online: May 21, 2015
Processing time: 212 Days and 17.6 Hours
AIM: To assess the prognostic significance of immunological and nutritional-based indices, including the prognostic nutritional index (PNI), neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio in gastric cancer.
METHODS: We retrospectively reviewed 632 gastric cancer patients who underwent gastrectomy between 1998 and 2008. Areas under the receiver operating characteristic curve were calculated to compare the predictive ability of the indices, together with estimating the sensitivity, specificity and agreement rate. Univariate and multivariate analyses were performed to identify risk factors for overall survival (OS). Propensity score analysis was performed to adjust variables to control for selection bias.
RESULTS: Each index could predict OS in gastric cancer patients in univariate analysis, but only PNI had independent prognostic significance in multivariate analysis before and after adjustment with propensity scoring (hazard ratio, 1.668; 95% confidence interval: 1.368-2.035). In subgroup analysis, a low PNI predicted a significantly shorter OS in patients with stage II-III disease (P = 0.019, P < 0.001), T3-T4 tumors (P < 0.001), or lymph node metastasis (P < 0.001). Canton score, a combination of PNI, NLR, and platelet, was a better indicator for OS than PNI, with the largest area under the curve for 12-, 36-, 60-mo OS and overall OS (P = 0.022, P = 0.030, P < 0.001, and P = 0.024, respectively). The maximum sensitivity, specificity, and agreement rate of Canton score for predicting prognosis were 84.6%, 34.9%, and 70.1%, respectively.
CONCLUSION: PNI is an independent prognostic factor for OS in gastric cancer. Canton score can be a novel preoperative prognostic index in gastric cancer.
Core tip: This is the first study to compare the prognostic significance of different immuno-nutritional indices including prognostic nutritional index (PNI), neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) in gastric cancer. We found that PNI was an independent prognostic factor for overall survival in gastric cancer before and after the propensity score analysis, especially in patients with advanced disease, deep tumors, or lymph node metastasis. We also proposed that a new index-Canton score (a combination of PNI, NLR and PLT) is a superior prognostic factor compared to PNI, NLR, or PLR alone, as it better represents the relative contribution of each of these indices.