Prognostic impact of prognostic nutritional index before radiotherapy in clinical stage Ⅲ esophageal cancer patients / 中华放射医学与防护杂志

ABSTRACT

Objective:To study the prognostic impact of prognostic nutritional index (PNI) before radiotherapy in clinical stage Ⅲ esophageal cancer patients.Methods:We retrospectively reviewed 125 esophageal cancer patients with clinical stage Ⅲ undergoing definitive radiotherapy in Fourth Hospital of Hebei Medical University from 2013 to 2017. The PNI and nutritional risk index (NRI) were calculated before radiotherapy. The optimal cutoff value of PNI was determined by time-dependent receiver operating characteristics (ROC) at 49.925.The patients were divided into low PNI group(PNI<49.925) and high PNI group (PNI≥49.925). Based on NRI, the patients were divided into normal NRI group (NRI≥100) and abnormal NRI group (NRI<100). Kaplan-Meier method was used to calculate the overall survival (OS) and progression-free survival (PFS) and to perform univariate analysis. The mutlivariate analysis was performed by Cox regression model.Results:PNI was positively correlated with hemoglobin ( r=0.505, P<0.001) and NRI ( r=0.594, P<0.001). The 1-, 3- and 5-year OS rates in the low PNI group were significantly lower than those of the high PNI group (67.5%, 27.3%, 11.4% vs. 85.4%, 45.8%, 27.4%, respectively, χ2=8.569, P<0.05). Moreover, the 1-, 3- and 5-year PFS rates in the low PNI group were obviously higher than those in the high PNI group (59.7%, 23.2%, 4.9% vs. 79.2%, 35.4%, 24.9%, respectively, χ2=6.715, P<0.05). Univariate analysis showed that GTV, radiotherapy dose, chemotherapy, albumin, NRI and PNI were significantly correlated with OS and PFS (OS χ2=6.822, 4.326, 4.474, 13.123, 8.846, 8.569, P<0.05 PFS χ2=7.869, 4.636, 5.874, 10.911, 8.544, 6.715, P<0.05). Multivariate analysis showed that GTV, radiotherapy dose and PNI were independent prognostic factors for OS ( P<0.05). And GTV, radiotherapy dose, chemotherapy and PNI were independent prognostic factors for PFS ( P<0.05). Conclusions:The PNI before radiotherapy is a significant and independent predictor for survival of clinical stage Ⅲ esophageal cancer patients. Based on simple and inexpensive standard laboratory measurements, PNI could be a promising prognostic biomarker for esophageal cancer patients.