Background: The clinical behavior of patients ith advanced non-small cell lung cancer  NSCLC  differ beteen epidermal groth factor receptor  EGFR  exon 19 deletion  Ex19  and EGFR exon 21 L858R mutation  Ex21 . This study aimed to evaluate hether these differences exist in surgically resected NSCLC. Methods: Patients received surgery for primary lung tumors in Zhejiang Cancer Hospital from Jan 1, 2011 to Dec 30, 2013 ere screened retrospectively. A total of 198 patients ith surgically resected NSCLC harbouring Ex19  n = 53 , Ex21  n = 51 , and EGFR ild-type  Wt   n = 94  ere analyzed. The clinicopathological features, laboratory parameters, recurrent sites and disease-free survival  DFS  ere compared according to mutational EGFR status. Results: Ex21 lesions occurred more frequently in female  plt0.001 , never-smokers  plt0.001 , adenocarcinoma  plt0.001 , lo grade  p=0.011  and had a higher pleural invasion rate  p=0.029  and loer vessel invasion rate  p=0.029  than Wt lesions. Ex19 lesions occurred more frequently in female  p=0.013 , never-smokers  p=0.006 , adenocarcinoma  plt0.001 , lo grade  p=0.023  than Wt lesions. Ex21 lesions occurred more frequently in never-smokers  p=0.034  than Ex19 lesions. Both Ex19  0.013  and Ex 21  0.041  had smaller mucinous variant components than Wt. Ex 21  0.016  had larger lepidic groth components than Wt. Ex21 lesions ere associated ith loer pretreatment neutrophil: lymphocyte ratio  NLR  than Wt lesions  p=0.017 . The recurrent sites and DFS ere similar among patients ith Wt, Ex19 and Ex21. Conclusions: While no significant difference in DFS as observed, the clinicopathological features ere different among Wt, Ex19 and Ex21 in surgically resected NSCLC.,J Clin Oncol 34, 2016  suppl; abstr e20043 ,Publication Only Lung CancerNon-Small Cell Local-RegionalSmall CellOther Thoracic Cancers