title: Impact of positive pleural lavage cytology on survival in patients having lung resection for non-small-cell lung cancer: An international individual patient data meta-analysis.
abstract: OBJECTIVE
  Pleural lavage cytology is the microscopic study of cells obtained from saline instilled into and retrieved from the chest during surgery for non-small-cell lung cancer. The aims of this study were to collate multi-institutional individual patient data for meta-analysis to determine independence as a prognostic marker and to characterize the impact of positive results on stage-adjusted survival.
  
  
  METHODS
  We identified 31 publications from 22 centers/research groups that performed pleural lavage cytology during surgery for non-small-cell lung cancer and invited submission of individual patient data. Actuarial survival was calculated using Kaplan-Meier methods, and comparisons were performed using the log-rank test. Cox proportional hazards regression was used to ascertain the covariates associated with survival.
  
  
  RESULTS
  By January 1, 2008, submissions were received internationally from 11 centers with individual data from 8763 patients. In total, 511 (5.8%) patients had a positive pleural lavage cytology result, and this was shown to be an independent predictor of adverse survival associated with a hazard ratio of 1.465 (1.290-1.665; P < .001) compared with a reference hazard ratio of 1 for a negative result. On statistical modeling, the best adjustment for patients with a positive pleural lavage cytology result was a single increase in the T category assigned to the case, up to a maximum of T4. Correction for differences in survival were obtained in stages IB (P = .315) and IIB (P = .453), with a degree of correction in stage IIIA (P = .07).
  
  
  CONCLUSIONS
  Pleural lavage cytology should be considered in all patients with non-small-cell lung cancer suitable for resection. A positive result is an independent predictor of adverse survival, and the impact on survival suggests that it may be appropriate to upstage patients by 1 T category.
authors: Eric
authors: E
authors: Lim
authors: Rachel
authors: R
authors: Clough
authors: Peter
authors: P
authors: Goldstraw
authors: Lyn
authors: L
authors: Edmonds
authors: Keiju
authors: K
authors: Aokage
authors: Junji
authors: J
authors: Yoshida
authors: Kanji
authors: K
authors: Nagai
authors: Yasushi
authors: Y
authors: Shintani
authors: Mitsunori
authors: M
authors: Ohta
authors: Meinoshin
authors: M
authors: Okumura
authors: Teruo
authors: T
authors: Iwasaki
authors: Tsutomu
authors: T
authors: Yasumitsu
authors: Morihito
authors: M
authors: Okada
authors: Takeshi
authors: T
authors: Mimura
authors: Noriaki
authors: N
authors: Tsubota
authors: Tatsuo
authors: T
authors: Nakagawa
authors: Norihito
authors: N
authors: Okumura
authors: Yukitoshi
authors: Y
authors: Satoh
authors: Sakae
authors: S
authors: Okumura
authors: Ken
authors: K
authors: Nakagawa
authors: Masahiko
authors: M
authors: Higashiyama
authors: Ken
authors: K
authors: Kodama
authors: Marc
authors: M
authors: Riquet
authors: Giovanni
authors: G
authors: Vicidomini
authors: Mario
authors: M
authors: Santini
authors: Christophoros
authors: C
authors: Kotoulas
authors: Jeng-Yuan
authors: JY
authors: Hsu
authors: Chih-Yi
authors: CY
authors: Chen
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D010994:Pleura; D011013:Pneumonectomy; D011379:Prognosis; D015996:Survival Rate; D007507:Therapeutic Irrigation