title: Retrospective study of erlotinib in patients with advanced squamous lung cancer.
abstract: BACKGROUND
  The effective targeted therapy for lung squamous cell carcinoma (SCC) is needed. The epidermal growth factor receptor (EGFR) mutation rate is low in lung SCC. The aim of this study was to evaluate the status of erlotinib treatment and EGFR mutation in lung SCC patients.
  
  
  METHODS
  We retrospectively enrolled lung cancer patients with SCC histology and history of erlotinib treatment. The primary objective was to assess overall response rate (ORR) and disease control rate (DCR) and the secondary objective was to assess progression-free survival (PFS) and overall survival (OS). EGFR mutations were assessed in parts of patients using both direct sequencing and protein nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamp methods.
  
  
  RESULTS
  In total, 92 patients were analyzed (75 men and 17 women, median age 69 years, and 74 current or former smokers). Sixteen patients achieved partial response and 9 had stable disease. The ORR was 17.4% and the DCR was 27.2%. The PFS and OS were longer in patients with disease control than with progressive disease (PFS 7.8 versus 1.3 months and OS 20.7 versus 2.7 months, both p<0.0001). The 1-year survival rate was 21.7%. In 27 patients with adequate specimens for molecular analysis (including 4 PR and 4 SD), two (7.4%) had EGFR complex mutations. One patient experienced response to erlotinib and the other did not.
  
  
  CONCLUSIONS
  A significant proportion of lung SCC patients would derive a clinical benefit from erlotinib treatment. The relatively higher response rate than the EGFR mutation rate in present study needs further evaluation.
authors.affiliation: Division of Chest Medicine, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan; Institute of Biomedical Sciences, National Chung-Hsing University, Taichung, Taiwan.
authors.forename: Jeng-Sen
authors.initials: JS
authors.lastname: Tseng
authors.forename: Tsung-Ying
authors.initials: TY
authors.lastname: Yang
authors.forename: Kun-Chieh
authors.initials: KC
authors.lastname: Chen
authors.forename: Kuo-Hsuan
authors.initials: KH
authors.lastname: Hsu
authors.forename: Hsuan-Yu
authors.initials: HY
authors.lastname: Chen
authors.forename: Gee-Chen
authors.initials: GC
authors.lastname: Chang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D004252:DNA Mutational Analysis; D018572:Disease-Free Survival; D066246:ErbB Receptors / Q000235:genetics; D000069347:Erlotinib Hydrochloride; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D011799:Quinazolines / Q000627:therapeutic use*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D011799:Quinazolines; D000069347:Erlotinib Hydrochloride; C512478:EGFR protein, human; D066246:ErbB Receptors