P1.17-02 Low Prognostic Nutritional Index Predicts Poor Survival in Stage IIIB Non-Small Cell Lung Cancer Patients Treated with Chemoradiotherapy

Abstract

The prognostic role of prognostic nutritional index (PNI) has been widely investigated and showed in many types of cancer. However, to our best knowledge, the significance of PNI has never been investigated in locally advanced non-small cell lung cancer (NSCLC) who were treated with concurrent chemoradiotherapy ( CCRT). Therefore in this current study, we aimed to investigate the prognostic impact of PNI on survival outcomes of locally advanced NSCLC undergoing CCRT. The data of 358 patients with stage IIIB NSCLC treated with CCRT were analyzed retrospectively. All patients received 60 to 66 Gy (2 Gy per fraction) thoracic radiotherapy and at least one course of platinum-based doublet chemotherapy concomitantly. For each patient PNI was calculated by the known formula in blood samples those were available prior to CCRT: [PNI=10×serum albumin (g/dl) + 0.005×total lymphocyte count (mm3)]. The primary endpoint was the association between PNI and overall survival (OS). Secondary endpoints were locoregional progression-free survival (LPFS) and progression-free survival (PFS). The survival curves were calculated by Kaplan-Meier method and log-rank test. The cutoff value of the PNI was analyzed by receiver operating curve (ROC). At a median follow-up of 22.5 months (2.4-123.5 months) 108 patients (30.2%) were still alive. For the whole study cohort median OS was 25.2 months (95 % CI: 22.7-27.7). The median LPFS and PFS were 15.4 months (95% CI: 14.4-16.4) and 10.7 months (95% CI: 9.7-11.7) respectively. In ROC analysis, calculated cutoff value of PNI was 40.1 (AUC: 67.8% (62.0-73.6); sensitivity: 73.1; specificity: 68.4, p<0.001). According to this, patients were grouped as follows, group 1: PNI>40 and group 2: PNI<40. Accordingly, for the patients in group 1, OS (36.7 vs. 16.8 months, p<0.001), LPFS (19.5 vs. 11.5 months, p<0.001) and PFS (13.6 vs. 8.6 months, p<0.001) times were significantly better as compared to patients in group 2. Results of the multivariate analysis demonstrated that the prognostic worth of PNI was independent of the other covariates (p<0.001, for each survival endpoints). Being the first of its kind study the result of this current investigation revealed that the PNI which is easy to calculate, easily achievable with no additional cost has a strong prognostic value in prognostic stratification of the stage IIIB NSCLC patients undergoing to CCRT.