title: The clinical outcome of non-small cell lung cancer patients with adjacent lobe invasion: the optimal classification according to the status of the interlobar pleura at the invasion point.
abstract: OBJECTIVE
  The aim of this study was to analyse the survival of non-small cell lung cancer (NSCLC) patients with adjacent lobe invasion (ALI) with emphasis on the interlobar fissure status at the tumour invasion point.
  
  
  METHODS
  We retrospectively evaluated 2097 consecutive patients with surgically resected NSCLC from July 1993 through April 2006. Of these, 90 (4.3%) patients had tumours with ALI. We divided ALIs into two types by histological examination using elastic stains: direct ALI beyond the incomplete fissure (ALI-D, n = 18) and ALI across the interlobar fissure (ALI-A, n = 72), and compared the clinicopathological features and survival.
  
  
  RESULTS
  The patients with ALI demonstrated an intermediate survival between T2a and T2b tumours (5-year overall survival: T2a, 61.0%; ALI, 59.6%; T2b, 49.2%). There were distinct survival differences between the patients with ALI-A and ALI-D (5-year overall survival: ALI-D, 85.7%; ALI-A, 52.0%; P = 0.010). The survival of patients with ALI-A was not statistically different from that of patients with T2b tumours, regardless of the tumour size (P = 0.846). The survival of the patients with ALI-D did not statistically differ from those with T1a or T1b tumours (P = 0.765 and 0.418, respectively).
  
  
  CONCLUSIONS
  Our results indicate that the interlobar fissure status affects the survival of the patients with ALI. ALI should be examined by elastic stains and only ALI-A should be classified as true ALI. We propose that ALI-A tumours with a size of ≤ 5 cm should be assigned to T2b, but ALI-D tumours do not require an adjustment of the T descriptor.
authors.affiliation: Division of Thoracic Surgery,  National Cancer Centre Hospital East, Chiba,  Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ohtaki
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Hishida
authors.forename: Junji
authors.initials: J
authors.lastname: Yoshida
authors.forename: Genichiro
authors.initials: G
authors.lastname: Ishii
authors.forename: Akikazu
authors.initials: A
authors.lastname: Kawase
authors.forename: Keiju
authors.initials: K
authors.lastname: Aokage
authors.forename: Mitsuyo
authors.initials: M
authors.lastname: Nishimura
authors.forename: Kanji
authors.initials: K
authors.lastname: Nagai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010994:Pleura / Q000473:pathology*; D010997:Pleural Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D011182:Postoperative Care; D012189:Retrospective Studies; D055815:Young Adult