P068 The Geriatric Nutritional Risk Index Predicts the Overall Survival in Geriatric Patients with Metastatic Lung Adenocarcinoma

Abstract

Metastatic lung adenocarcinoma patients have poor prognosis. Many factors are associated with the prognosis of lung cancer patients, including nutrition status. Geriatric nutrition risk index (GNRI) is a simplified, objective screening parameter for nutrition risk in geriatric patients. The aim of this study was to assess the prognostic value of pretreatment GNRI in geriatric patients with metastatic lung adenocarcinoma, which has not been reported before. The clinical and pathological data of 144 consecutive geriatric patients with metastatic lung adenocarcinoma between January 2011 and May 2017 were retrospectively analyzed. The pretreatment GNRI was calculated as follows: GNRI=1.489×pretreatment serum albumin concentration (g/L)+41.7×pretreatment body weight(kg)/ideal body weight(kg); ideal body weight(kg)=Height-100-[(Height-150)/4](for men) or Height-100-[(Height-150)/2.5](for women); when pretreatment body weight exceeded ideal body weight, pretreatment body weight/ideal body weight was set to 1. The receiver operating characteristic (ROC) curve was used to determine the best cutoff value of GNRI for predicting OS. The Kaplan–Meier method with Log-rank test was used to estimate survival curves. Univariate and multivariate Cox regression were used to identify variables associated with overall survival (OS) in the whole cohort, EGFR wildtype subgroup and EGFR mutation subgroup, respectively. According to ROC results, the patients were divided into malnutrition risk group (MNRG) (GNRI≤97, N=75) and normal nutrition group(NNG) (GNRI>97, N=69). Low GNRI value was significantly associated with older age (P=0.002) and high ECOG score (P=0.037). In Kaplan-Meier analysis of OS, NNG had significantly longer OS compared to the MNRG (1-year OS, 85.6%vs.54.7%, P<0.0001) in the whole cohort. In EGFR wildtype subgroup (N=60), the normal nutrition patients had significantly longer OS compared to the malnutrition risk patients (1-year OS, 77.5%vs.36.4%, P<0.0001). In the EGFR mutation group (N=84), the normal nutrition group had longer OS than the malnutrition risk patients, but did not reach significance (1-year OS, 96.6%vs.80.6%, P=0.099). Univariate and multivariate Cox regression analyses showed that low GNRI value (P=0.019), liver metastases(P<0.0001), EGFR mutation status(P<0.0001) were independent prognostic factors of OS. Further analysis showed that low GNRI value (P=0.025), liver metastases (P<0.0001), ECOG (P=0.008) were independent prognostic factors of OS in the EGFR wildtype subgroup, and gender (P=0.007) was independent prognostic factor for OS in the EGFR mutation subgroup. This study confirmed the importance of pretreatment GNRI in predicting the OS in geriatric patients with metastatic lung adenocarcinoma, especially in the patients not harboring EGFR mutations.