title: Smoking History as a Predictor of Pemetrexed Monotherapy in Patients with Non-Squamous Non-Small Cell Lung Cancer.
abstract: BACKGROUND
  Pemetrexed monotherapy has come to be recognized as the standard of care for second-line therapy of non-squamous non-small cell lung cancer (NSCLC). Thymidylate synthase (TS) expression is recognized as a potential predictor of the response to pemetrexed-based chemotherapy in patients with advanced NSCLC. The purpose of this study was to identify useful predictors of the response to pemetrexed other than TS expression.
  
  
  METHODS
  The records of non-squamous NSCLC patients without driver mutations who received pemetrexed monotherapy as a second or later line of chemotherapy at Kitasato University Hospital between March 2009 and October 2015 were retrospectively reviewed, and the treatment outcomes were evaluated.
  
  
  RESULTS
  In the 116 patients with non-squamous NSCLC, the overall response rate and progression-free survival (PFS) were 10.3% and 2.1 months, respectively. The disease control rate and PFS differed significantly among current smokers and never-smokers/former light smokers (44.9 vs. 65.8%, and 1.8 vs. 4.0 months, respectively). Furthermore, multivariate analysis identified Eastern Cooperative Oncology Group Performance Status and smoking status as independent predictors of the PFS.
  
  
  CONCLUSIONS
  The clinical data obtained in this study may provide a valuable basis for the use of smoking status as a predictor of pemetrexed monotherapy in wild-type NSCLC patients.
authors.affiliation: Department of Respiratory Medicine, Kitasato University School of Medicine, Sagamihara, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Igawa
authors.forename: Jiichiro
authors.initials: J
authors.lastname: Sasaki
authors.forename: Sakiko
authors.initials: S
authors.lastname: Otani
authors.forename: Masayuki
authors.initials: M
authors.lastname: Shirasawa
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Niwa
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Kusuhara
authors.forename: Shinya
authors.initials: S
authors.lastname: Harada
authors.forename: Masaru
authors.initials: M
authors.lastname: Kubota
authors.forename: Masato
authors.initials: M
authors.lastname: Katagiri
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Masuda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy*; D015331:Cohort Studies; D018572:Disease-Free Survival; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008175:Lung Neoplasms / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D000068437:Pemetrexed / Q000627:therapeutic use*; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects / Q000503:physiopathology*
chemical_list: D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D000068437:Pemetrexed