title: Survival outcome assessed according to tumor burden and progression patterns in patients with epidermal growth factor receptor mutant lung adenocarcinoma undergoing epidermal growth factor receptor tyrosine kinase inhibitor therapy.
abstract: BACKGROUND
  Mutations in the epidermal growth factor receptor (EGFR) have been associated with a marked therapeutic response to EGFR-tyrosine kinase inhibitors (TKIs) in patients with advanced non-small-cell lung cancer (NSCLC). However, the clinical predictors of the survival benefit of EGFR-TKI therapy for NSCLC with EGFR-activating mutations have not been well elucidated. Therefore, the present study evaluated the clinical predictors of survival outcome in patients with EGFR-mutant NSCLC who had been treated with EGFR-TKIs.
  
  
  METHODS
  The data from 224 patients with EGFR-mutant lung adenocarcinoma treated with EGFR-TKIs were retrospectively reviewed. The treatment outcomes were evaluated according to the clinical factors, number of metastasis sites, and progression patterns.
  
  
  RESULTS
  The clinical factors associated with reduced progression-free survival (PFS) and overall survival (OS) on univariate analysis were Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≥ 2, intra- and extrathoracic metastasis, extrathoracic metastasis, a high number of metastatic sites, metastasis to the liver or adrenal gland at baseline, and rapid progression at the diagnosis of progressive disease (PD). On multivariate analysis, the factors that remained significantly associated with a shorter PFS were ECOG PS ≥ 2 (odds ratio [OR], 2.189; 95% confidence interval [CI], 1.374-3.437; P < .001) and rapid tumor progression at PD (OR, 1.800; 95% CI, 1.059-3.058; P = .030).
  
  
  CONCLUSIONS
  Thus, the tumor burden, expressed as the number of metastatic sites at EGFR-TKI treatment, and rapid tumor progression at PD were predictive of inferior survival in patients with lung adenocarcinoma with activating EGFR mutations.
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yoon Ki
authors.initials: YK
authors.lastname: Cha
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. Electronic address: hoyunlee96@gmail.com.
authors.forename: Ho Yun
authors.initials: HY
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Myung-Ju
authors.initials: MJ
authors.lastname: Ahn
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yoon-La
authors.initials: YL
authors.lastname: Choi
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Keunchil
authors.initials: K
authors.lastname: Park
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyung Soo
authors.initials: KS
authors.lastname: Lee
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality* / Q000473:pathology; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D018450:Disease Progression; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use*; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome; D047368:Tumor Burden
chemical_list: D000970:Antineoplastic Agents; D047428:Protein Kinase Inhibitors; C512478:EGFR protein, human; D066246:ErbB Receptors
keywords: Epidermal growth factor receptor; Non–small-cell lung cancer; Predictor; Tumor burden; Tyrosine kinase inhibitor