Prognostic signature of early lung adenocarcinoma based on the expression of ribonucleic acid metabolism–related genes

Abstract

ObjectiveThe current staging system for lung cancer is not sufficient to accurately identify those patients with early-stage tumors who would benefit from postsurgery chemotherapy. The objective of this study was to validate a prognostic signature based on the expression of 5 RNA (ribonucleic acid) metabolism-related genes. MethodsFive lung cancer microarray datasets, 3 from adenocarcinomas and 2 from squamous cell carcinomas, were analyzed. Kaplan-Meier survival curves and Cox proportional hazards models were used to evaluate the relationship between the classifier and recurrence and survival. ResultsStatistically significant differences in relapse-free survival and overall survival were observed when lung adenocarcinoma patients were divided into 3 risk groups. The prognostic information provided by the signature was independent from other demographic and disease variables, including stage. Significant differences in survival were observed between low- and high-risk groups in stage-IB patients: 5-year survival rates ranged from 83% to 100% in the low-risk groups, and from 30% to 71% in the high-risk groups, depending on the dataset. The RNA metabolism score additionally displayed an association with the benefit of adjuvant chemotherapy (P < .001), suggesting that those patients in the low-risk group are not good candidates for this treatment. ConclusionsThe RNA metabolism signature is a prognostic marker that may be useful for predicting survival and optimizing the benefit of adjuvant chemotherapy in patients with lung adenocarcinoma.