title: Long-term survival and risk factors for recurrence in stage I non-small cell lung cancer patients with tumors up to 3 cm in maximum dimension.
abstract: BACKGROUND
  The purpose of this study was to evaluate patients with stage I non-small cell lung cancer (NSCLC) and tumors up to 3 cm in maximum dimension who underwent surgical resection on the revised TNM classification and to investigate the risk factors for recurrence.
  
  
  METHODS
  Between 1994 and 2003, 713 consecutive stage I NSCLC patients with tumors up to 3 cm in maximum dimension underwent complete resection. Recurrence-free probability was estimated from the date of the primary tumor resection to the date of the first recurrence or the last follow-up using the Kaplan-Meier method.
  
  
  RESULTS
  The recurrence-free probability of stage I NSCLC patients with tumors up to 3 cm in maximum dimension was 87% at 5 years. On multivariate analyses, three variables were shown to be independently significant recurrence risk factors: histologic differentiation (hazard ratio, 2.3), intratumoral vessel invasion (hazard ratio, 2.9), and visceral pleural invasion (VPI) (hazard ratio, 1.8). According to subgroup analyses combining these three risk factors, the 5-year recurrence-free probability was 94% for patients with zero or one factor (n = 492) and 71% for patients with two or three factors (n = 221), respectively (P < .001).
  
  
  CONCLUSIONS
  In stage I NSCLC patients with tumors up to 3 cm in maximum dimension, we identified three risk factors for recurrence that independently increase their risk of recurrence. In addition to VPI, histologic differentiation and intratumoral vessel invasion should be examined and their data collected for the next revision of the TNM staging system.
authors.affiliation: Department of Thoracic Oncology, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, Chiba 277-8577, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Maeda
authors.forename: Junji
authors.initials: J
authors.lastname: Yoshida
authors.forename: Genichiro
authors.initials: G
authors.lastname: Ishii
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Hishida
authors.forename: Keiju
authors.initials: K
authors.lastname: Aokage
authors.forename: Mitsuyo
authors.initials: M
authors.lastname: Nishimura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Nishiwaki
authors.forename: Kanji
authors.initials: K
authors.lastname: Nagai
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011379:Prognosis; D012307:Risk Factors; D016019:Survival Analysis