title: Factors affecting tumor recurrence after curative surgery for NSCLC: impacts of lymphovascular invasion on early tumor recurrence.
abstract: BACKGROUND
  Although surgery is potentially curative treatment for non-small cell lung cancer (NSCLC), the risk of postoperative disease recurrence is still high. This study was conducted to assess the factors associated with postoperative tumor recurrence in patients who underwent curative surgery for NSCLC.
  
  
  METHODS
  One hundred seventy-one patients who underwent curative surgery for NSCLC were included in this study. Clinicopathological factors of histologic type, pathologic TNM stage, T stage, N stage, lymphovascular invasion (LVI), perineural invasion (PNI), surgical procedure, adjuvant chemotherapy and adjuvant radiotherapy were investigated. Gender, age, and clinicopathologic factors were included in univariate and multivariate analyses using the Kaplan-Meier method and Cox proportional hazards model, respectively. Mann-Whitney U and Kruskal-Wallis tests were used to investigate the significance of differences in recurrence-free interval (RFI) according to clinicopathological factors.
  
  
  RESULTS
  Median RFI was 20 months. Univariate and multivariate analyses for overall recurrence identified T stage, N stage, and LVI as significant factors (P=0.045, 0.044, and <0.001, respectively). Pathologic stage (P=0.005) was the only factor that was significantly associated with locoregional recurrence. T stage (P=0.040) and LVI (P<0.001) were significantly associated with distant recurrence. The difference in 2-year freedom from recurrence between LVI positive and negative groups was significant (14.9% vs. 44.6%, P<0.001). LVI was the only factor that was significantly associated with a shortened mean RFI (P<0.001).
  
  
  CONCLUSIONS
  LVI had a significant effect on both overall and distant recurrence rates as well as on early tumor recurrence after curative surgery for NSCLC.
authors.affiliation: 1 Department of Radiology, 2 Department of Internal Medicine, 3 Department of Thoracic Surgery, Hallym University College of Medicine, Chuncheon, Republic of Korea.
authors.forename: Chanyeong
authors.initials: C
authors.lastname: Park
authors.affiliation: 1 Department of Radiology, 2 Department of Internal Medicine, 3 Department of Thoracic Surgery, Hallym University College of Medicine, Chuncheon, Republic of Korea.
authors.forename: In Jae
authors.initials: IJ
authors.lastname: Lee
authors.affiliation: 1 Department of Radiology, 2 Department of Internal Medicine, 3 Department of Thoracic Surgery, Hallym University College of Medicine, Chuncheon, Republic of Korea.
authors.forename: Seung Hun
authors.initials: SH
authors.lastname: Jang
authors.affiliation: 1 Department of Radiology, 2 Department of Internal Medicine, 3 Department of Thoracic Surgery, Hallym University College of Medicine, Chuncheon, Republic of Korea.
authors.forename: Jae Woong
authors.initials: JW
authors.lastname: Lee
keywords: Thorax; lung; metastases; pathology; surgery