title: Early radiographic response to epidermal growth factor receptor-tyrosine kinase inhibitor in non-small cell lung cancer patients with epidermal growth factor receptor mutations: A prospective study.
abstract: BACKGROUND
  The time schedules for response evaluation of epidermal growth factor receptor-tyrosine kinase Inhibitor (EGFR-TKI) in non-small cell lung cancer (NSCLC) patients are still ill-defined.
  
  
  METHODS
  Stage IIIB/IV patients with histologically proven NSCLC were enrolled in this study if the tumor cells bore EGFR mutations other than T790M. Eligible patients were treated with either 250 mg of gefitinib or 150 mg of erlotinib once daily. The early response rate [computed tomography (CT) scan on Day 14], definitive response rate determined on Day 56, progression-free survival (PFS), overall survival (OS), and toxicity profile were assessed prospectively.
  
  
  RESULTS
  Thirty-nine patients were enrolled in this study. A total of 29 patients (29/39, 74.4%) achieved partial response (PR). Twenty-one patients (21/39, 53.8%) had early radiological response on Day 14. The early radiological response rate in patients with PR was 72.4% (21/29). Only eight patients without a PR on early CT still ended with PR. Among the 29 patients with PR, the PFS (8.1 months) and OS (18.3 months) of the 21 patients with early CT response were shorter than those of the 8 patients without early CT response (11.9 and 24.0 months for PFS and OS, respectively). But the survival differences were statistically non-significant.
  
  
  CONCLUSIONS
  A very high percentage (72.4%, 21/29) of NSCLC patients with EGFR mutations with PR demonstrates early radiological response to EGFR-TKIs, which would advocate early radiological examination for EGFR-TKI therapy in NSCLC patients.
authors.forename: John W C
authors.initials: JW
authors.lastname: Chang
authors.forename: Ming-Mo
authors.initials: MM
authors.lastname: Hou
authors.forename: Jia-Juan
authors.initials: JJ
authors.lastname: Hsieh
authors.forename: Yun-Chung
authors.initials: YC
authors.lastname: Cheung
authors.forename: Hung-Ming
authors.initials: HM
authors.lastname: Wang
authors.forename: Jen-Shi
authors.initials: JS
authors.lastname: Chen
authors.forename: Cheng-Hsu
authors.initials: CH
authors.lastname: Wang
authors.forename: Chih-Hung
authors.initials: CH
authors.lastname: Chen
authors.forename: Kun-Yun
authors.initials: KY
authors.lastname: Yeh
authors.forename: Li-Ying
authors.initials: LY
authors.lastname: Ou
authors.forename: Chia-Hsun
authors.initials: CH
authors.lastname: Hsieh
authors.forename: Hong-Dar Isaac
authors.initials: HD
authors.lastname: Wu
authors.forename: Ying-Tsong
authors.initials: YT
authors.lastname: Chen
authors.forename: Il-Chi
authors.initials: IC
authors.lastname: Chang
authors.affiliation: Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan; Department of Pathology, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan; Department of Pathology, Tzu-Chi Medical Center, Taipei Branch, Tzu-Chi University, Taipei, Taiwan.
authors.forename: Shiu-Feng
authors.initials: SF
authors.lastname: Huang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000532:radiotherapy; D018572:Disease-Free Survival; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics*; D000069347:Erlotinib Hydrochloride / Q000627:therapeutic use*; D005260:Female; D000077156:Gefitinib; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000532:radiotherapy; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011446:Prospective Studies; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use*; D011799:Quinazolines / Q000627:therapeutic use*; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000970:Antineoplastic Agents; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D000069347:Erlotinib Hydrochloride; C512478:EGFR protein, human; D066246:ErbB Receptors; D000077156:Gefitinib