title: Prognostic impact of pleural lavage cytology in patients with primary lung cancer.
abstract: Positive pleural lavage cytology (PLC) has been reported to have a negative prognostic impact in patients with surgically resected non-small cell lung cancer (NSCLC). However, positive PLC does not upgrade the stage according to the 7th edition of TNM classification for lung cancer. The objectives of this study were to evaluate the prognostic impact of positive PLC in patients with NSCLC and to clarify its contribution to TNM classification.
  
  
  
  Seven hundred fifty-four patients who underwent surgical resection of NSCLC from January 2007 through December 2013 were retrospectively studied. PLC was performed using 50ml of saline immediately after thoracotomy.
  
  
  
  Thirty-eight of the 754 patients were positive for PLC (5.1%). The overall survival (OS) of patients with positive PLC was significantly shorter than that of those with negative PLC (P=0.007, log-rank test). In multivariate analyses of OS, positive PLC was a significant independent prognostic factor (hazard ratio=2.21, 95% confidence interval: 1.21-4.04, P=0.009). The OS of patients with positive PLC was significantly shorter than that of those with negative PLC and pT1 (P<0.0001) or negative PLC and pT2 (P<0.0001) and almost overlapped with that of those with negative PLC and pT3 disease (P=0.601).
  
  
  
  Positive PLC is an independent prognostic factor in patients with resected NSCLC. Based on our analyses, we propose that patients with positive PLC be staged as pT3.
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Tomizawa
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Masaya
authors.initials: M
authors.lastname: Nishino
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Sesumi
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Kobayashi
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Sato
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Chiba
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Shimoji
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Suda
authors.affiliation: Department of Pathology, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Shimizu
authors.affiliation: Department of Pathology, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Sato
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Takemoto
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Kindai University Faculty of Medicine, Ohno-Higashi, Osaka-Sayama, Japan. Electronic address: mitsudom@surg.med.kindai.ac.jp.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Mitsudomi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology*; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D035422:Pleural Cavity / Q000473:pathology*; D011379:Prognosis; D012189:Retrospective Studies; D013908:Thoracotomy / Q000379:methods
keywords: Non-small cell lung cancer; Pleural lavage cytology; Prognostic; TNM classification