title: Prognostic value of intraoperative pleural lavage cytology for non-small cell lung cancer: the influence of positive pleural lavage cytology results on T classification.
abstract: OBJECTIVE
  Although positive pleural lavage cytology (PLC) has been demonstrated to be closely associated with a poor prognosis for patients with lung cancer, it has not been incorporated into the TNM staging system of the Union for International Cancer Control. The aim of our study was to retrospectively examine the clinical significance of PLC status and illustrate the recommendations of the International Pleural Lavage Cytology Collaborators (IPLCC) in a large national database.
  
  
  METHODS
  The Japanese Joint Committee of Lung Cancer Registry database included 11,073 patients with non-small cell lung cancer who underwent resections in 2004. We extracted the clinicopathologic data for 4171 patients (37.3%) who underwent PLC. These patients were staged according to the seventh edition of the Union for International Cancer Control TNM classification and by recommendations of the IPLCC, in which T was singly upgraded up to a maximum of T4 for those who were PLC-positive. Prognoses based on these 2 systems were compared.
  
  
  RESULTS
  A total of 217 patients (5.2%) were PLC-positive, which was significantly associated with a higher incidence of adenocarcinoma and advanced disease. The 5-year survival for patients with positive and negative PLC results were 44.5% and 72.8%, respectively, and this difference in survival was statistically significant (P < .001). Multivariate analysis showed that positive PLC status was an independent factor for a poor prognosis (hazard ratio, 1.57; P < .001). Significant differences in survival were also found between patients with positive and negative PLC results in the same T categories and stages, including T2a, T3, stage IB, and stage IIIA. The IPLCC recommendations adjusted the prognostic differences in all T categories and stages. The significant difference in survival disappeared between the 2 groups in all T categories and stages.
  
  
  CONCLUSIONS
  Our results indicate that a T category upgrade is prognostically adequate for patients who are PLC-positive.
authors.affiliation: Department of Thoracic Surgery, Kurashiki Central Hospital, Kurashiki, Japan. Electronic address: kk8724@kchnet.or.jp.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Kameyama
authors.affiliation: Department of Thoracic Surgery, Kurashiki Central Hospital, Kurashiki, Japan.
authors.forename: Norihito
authors.initials: N
authors.lastname: Okumura
authors.affiliation: Department of Mathematics, Science University of Tokyo, Tokyo, Japan.
authors.forename: Etsuo
authors.initials: E
authors.lastname: Miyaoka
authors.affiliation: Division of Thoracic Surgery, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Hisao
authors.initials: H
authors.lastname: Asamura
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yoshino
authors.affiliation: Division of General Thoracic Surgery, Osaka City General Hospital, Osaka, Japan.
authors.forename: Hirohito
authors.initials: H
authors.lastname: Tada
authors.affiliation: Department of Oncology, Immunology, and Surgery, Nagoya City University Graduate School of Medical Science and Medical School, Nagoya, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Fujii
authors.affiliation: Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Nakanishi
authors.affiliation: Department of Medical Oncology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Eguchi
authors.affiliation: Department of Pulmonary Medicine, Sapporo-Kosei General Hospital, Hokkaido, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Mori
authors.affiliation: Division of Respiratory Disease, National Defense Medical College, Saitama, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Kobayashi
authors.affiliation: Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Noriyoshi
authors.initials: N
authors.lastname: Sawabata
authors.affiliation: Department of General Thoracic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Meinoshin
authors.initials: M
authors.lastname: Okumura
authors.affiliation: Department of Thoracic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Yokoi
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D007430:Intraoperative Care; D007564:Japan; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D035422:Pleural Cavity / Q000473:pathology*; D011013:Pneumonectomy / Q000009:adverse effects / Q000401:mortality; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D007507:Therapeutic Irrigation / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome