title: Usual interstitial pneumonia with lung cancer: clinicopathological analysis of 43 cases.
abstract: BACKGROUND
  Previous studies have suggested an association between usual interstitial pneumonia (UIP) and lung cancer (Ca). However, clinical and histological information is not enough to determine such an association, due to the low incidence and short survival time of patients with both conditions.
  
  
  METHODS
  We retrospectively reviewed the clinical and histological records of Ca patients with UIP between January 1999 and August 2013 at the Samsung Medical Center, Seoul, Korea. We found 43 patients who had Ca with UIP (UIP-Ca). Previously reported data of eighty-four patients with UIP-only were included as a comparison group.
  
  
  RESULTS
  Smoking is related to poor prognosis in patients with UIP-Ca, and the number of patients with a high smoking index of more than 30 pack-years significantly increased in UIP-Ca patients compared with UIP-only patients. There is no significant prognostic differentiation between UIP-Ca patients and UIP-only patients. Microscopically, UIP-Ca patients showed characteristically heterogeneous histological patterns and degrees of differentiation. There were many foci of squamous metaplasia or dysplasia at the peripheral area of squamous cell carcinomas.
  
  
  CONCLUSIONS
  We report 43 cases of UIP-Ca. Our results suggest that smoking is related to cancer occurrence in UIP patients and poor prognosis in UIP-Ca patients.
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Dae Hyun
authors.initials: DH
authors.lastname: Song
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: In Ho
authors.initials: IH
authors.lastname: Choi
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sang Yun
authors.initials: SY
authors.lastname: Ha
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kang Min
authors.initials: KM
authors.lastname: Han
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jae Jun
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Min Eui
authors.initials: ME
authors.lastname: Hong
authors.affiliation: Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyeongman
authors.initials: K
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Man Pyo
authors.initials: MP
authors.lastname: Chung
authors.affiliation: Department of Thoracic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jhingook
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Joungho
authors.initials: J
authors.lastname: Han
keywords: Etiology; Idiopathic pulmonary fibrosis; Lung neoplasms; Metaplasia; Smoking; Survival