title: Predictive factors for a long-term response duration in non-squamous cell lung cancer patients treated with pemetrexed.
abstract: Pemetrexed is widely used for the treatment of advanced non-squamous non-small-cell lung cancer (NSCLC). However, factors that can predict the benefits of pemetrexed therapy have not yet been defined.
  
  
  
  We compared the clinical and molecule pathological characteristics of good and poor responders among a cohort of 1,848 non-squamous NSCLC patients who had received at least two cycles of pemetrexed therapy between November 2006 and February 2015. Among these cases, 92 good responders who were the top 5 % in terms of progression-free survival (PFS) and 222 poor responders who had progressive disease after only 2 cycles of therapy were selected for the analysis.
  
  
  
  The median PFS of the good responders was 29.9 months (range; 20.9-90.0) and the median number of cycle was 37 (range; 18-129). Although 53.5 % of patients showed stable disease (SD), this response was sustained (median PFS in SD, 29.6 months). A never-smoking status was related to better survival outcome, whereas EGFR mutation, two or more metastatic sites, and intra-abdominal metastasis were each associated with a poor PFS. ALK translocation showed a tendency for a positive impact on response to pemetrexed, whereas metastatic lesion to liver, adrenal gland or bone showed a tendency for a negative impact despite not reaching our threshold for statistical significance.
  
  
  
  Predictive factors, such as smoking status, the status of genetic alteration and tumor burden, should be considered when administering pemetrexed therapy for non-squamous NSCLC.
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.
authors.forename: Sojung
authors.initials: S
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Kyungpook National University Hospital, Kyungpook National University School of Medicine, 130 Dongdeok-ro, Jung-gu, Daegu, 41944, South Korea.
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.|Department of Oncology, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.
authors.forename: Chang-Min
authors.initials: CM
authors.lastname: Choi
authors.affiliation: Department of Oncology, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.
authors.forename: Dae Ho
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Department of Oncology, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.
authors.forename: Sang-We
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Department of Oncology, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.
authors.forename: Jung-Shin
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Pulmonary and Critical Care Medicine, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.
authors.forename: Woo Sung
authors.initials: WS
authors.lastname: Kim
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.
authors.forename: Se Hoon
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Asan Institute for Life Sciences, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea.
authors.forename: Jin Kyung
authors.initials: JK
authors.lastname: Rho
authors.affiliation: Department of Oncology, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-Dong, Songpa-gu, Seoul, 05505, South Korea. jclee@amc.seoul.kr.
authors.forename: Jae Cheol
authors.identifier: 0000-0001-5963-0259
authors.initials: JC
authors.lastname: Lee
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000235:genetics; D018572:Disease-Free Survival; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009362:Neoplasm Metastasis; D000068437:Pemetrexed / Q000008:administration & dosage* / Q000627:therapeutic use; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology*; D016019:Survival Analysis; D016896:Treatment Outcome; D047368:Tumor Burden
chemical_list: D000068437:Pemetrexed; C512478:EGFR protein, human; D066246:ErbB Receptors
keywords: Anaplastic lymphoma kinase; EGFR; Non-small-cell lung cancer; Pemetrexed; Prognosis; Progression-free survival