title: Concomitant Interstitial Lung Disease Is a Risk Factor for Pleural Invasion in Lung Cancer.
abstract: BACKGROUND
  Lung carcinoma is often associated with interstitial lung disease (ILD), and the prognosis of lung cancer accompanied by ILD is unfavorable. In this study, cases of patients with primary lung cancer with or without ILD were reviewed to analyze surgical outcome, with special interest in the conformity of clinical and pathologic stages, pathologic findings of pleural invasion, malignant pleurisy first detected at the time of thoracotomy, and survival.
  
  
  METHODS
  Retrospective chart review was performed for 1,264 primary lung cancer patients who underwent surgery from 2004 to 2015. Concomitant ILD was diagnosed by pathological examination or preoperative chest computed tomography findings.
  
  
  RESULTS
  ILD was found in 104 patients (8.2%) with primary lung cancer. Conformity of clinical and pathological stages in the ILD-positive patients was poor, with a lower kappa value than that for the 1,160 ILD-negative patients (0.34 versus 0.51). The ILD group had significantly higher incidences of pleural invasion and unexpected malignant pleurisy than did the non-ILD group (for pleural invasion, 49.0% versus 24.5%, p < 0.0001; for malignant pleurisy, 7.69% versus 1.47%, p < 0.0001). The 5-year overall survival rates of the ILD group showed significantly lower than those of the non-ILD group (45.2% versus 70.1%; p = 0.0014) after propensity score matching.
  
  
  CONCLUSIONS
  In lung cancer, the concomitant existence of ILD is a risk factor for pleural invasion. Concomitant ILD might cause underestimation of clinical staging, increase the chance of unexpected malignant pleurisy during surgery, and shorten survival time.
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hata
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan. Electronic address: hidemisuzukidesu@yahoo.co.jp.
authors.forename: Hidemi
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nakajima
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Tanaka
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Taiki
authors.initials: T
authors.lastname: Fujiwara
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Wada
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Takekazu
authors.initials: T
authors.lastname: Iwata
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Yoshida
authors.affiliation: Department of General Thoracic Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yoshino
mesh_terms: D000368:Aged; D002277:Carcinoma / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000150:complications* / Q000401:mortality / Q000473:pathology; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010994:Pleura / Q000473:pathology*; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D013908:Thoracotomy; D016896:Treatment Outcome