title: Prognostic and predictive value of the novel classification of lung adenocarcinoma in patients with stage IB.
abstract: OBJECTIVE
  Controversy remains exist for the effect of adjuvant chemotherapy (ACT) among stage IB lung adenocarcinoma patients. This study aimed to investigate the predictive value of the current lung adenocarcinoma classification system on benefit of ACT among patients with stage IB lung adenocarcinoma.
  
  
  METHODS
  A total of 928 pathological stage IB invasive adenocarcinoma patients with R0 resection were included in this study. Based on the predominant growth pattern present in the tumor, invasive adenocarcinomas with mixed histologic components were classified into five subtypes: lepidic (LEP), acinar (ACN), papillary (PAP), micropapillary (MIP) and solid (SOL). These five histologic subtypes were collapsed into three groups (LEP, ACN/PAP and SOL/MIP). Disease-free survival (DFS) and overall survival (OS) were analyzed to evaluate benefit from ACT in patients with different histologic patterns using the Kaplan-Meier approach and multivariable Cox models.
  
  
  RESULTS
  For all stage IB invasive adenocarcinoma patients, SOL/MIP subgroup presented the worst prognosis, and LEP subgroup showed approximately 100 % 5-year survival. ACT was associated with a better DFS (HR, 0.70; 95 % CI 0.51-0.96, p = .026) for all stage IB patients. In SOL/MIP subgroup, patients could benefit from ACT for a significant improved DFS (HR, 0.81; 95 % CI 0.49-1.35; p = .030), but not for OS (HR, 0.39; 95 % CI 0.12-1.30, p = .111). In ACN/PAP subgroup, there was no significant benefit from ACT for both DFS (HR, 0.76; 95 % CI 0.54-1.08, p = .125) and OS (HR, 0.81; 95 % CI 0.49-1.35, p = .421).
  
  
  CONCLUSIONS
  SOL/MIP predominant pattern was predictive for ACT benefit for DFS among invasive lung adenocarcinoma patients in stage IB.
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Jizhuang
authors.initials: J
authors.lastname: Luo
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Qingyuan
authors.initials: Q
authors.lastname: Huang
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Pulmonary Medicine, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Baohui
authors.initials: B
authors.lastname: Han
authors.affiliation: Department of Pathology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Heng
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Wentao
authors.initials: W
authors.lastname: Fang
authors.affiliation: Department of Shanghai Lung Tumor Clinic Center, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Qingquan
authors.initials: Q
authors.lastname: Luo
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Yunhai
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Pathology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Tianxiang
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, 270, Dong-An Road, Shanghai, 200032, China.
authors.forename: Xinghua
authors.initials: X
authors.lastname: Cheng
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Yiyang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Jiajie
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Department of Thoracic Surgery, Shanghai Ruijin Hosptial, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Han
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Thoracic Surgery, Shanghai Ruijin Hosptial, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Weicong
authors.initials: W
authors.lastname: Xia
authors.affiliation: Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China. hqchen1@yahoo.com.|Department of Thoracic Surgery, Fudan University Shanghai Cancer Center, 270, Dong-An Road, Shanghai, 200032, China. hqchen1@yahoo.com.|Institutes of Biomedical Sciences, Fudan University, Shanghai, China. hqchen1@yahoo.com.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China. hqchen1@yahoo.com.
authors.forename: Haiquan
authors.initials: H
authors.lastname: Chen
mesh_terms: D000230:Adenocarcinoma / Q000145:classification* / Q000473:pathology* / Q000628:therapy; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000145:classification* / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies
keywords: Adjuvant chemotherapy; Invasive lung adenocarcinoma; Non-small-cell lung cancer; Prognosis; Stage IB