The importance of novel molecular biomarker of early stage lung adenocarcinoma

Lung cancer is one of the most frequent human cancers and the leading cause of cancer related death worldwide compared with other solid tumors (1). Surgical resection is the standard treatment of patients with early stage nonsmall cell lung cancer (NSCLC). Despite curative intent surgical resection, tumor recurrence and metastasis remain the primary causes of cancer-related death (1). With the results of the National Lung Screening Trial, the detection rate and the opportunity of curative treatment for earlystage lung cancer is expected to increase. Based on this study, lung cancer mortality can be reduced if tumors are diagnosed in early stage (2). The overall prognostic outcome of early stage lung adenocarcinoma (ADC), which is the major pathological subtype of NSCLC, is favorable compared to advanced stage lung ADCs and other histological subtypes. However, up to 17% of these patients will eventually relapse within 5 years from initial surgery (3). Most of the reasons of the deaths are due to distant recurrence after surgical resection (3).