title: The value of CT for disease detection and prognosis determination in combined pulmonary fibrosis and emphysema (CPFE).
abstract: OBJECTIVE
  Several imaging-based indices were constructed quantitatively using the emphysema index (EI) and fibrosis score (FS) on high-resolution computed tomography (HRCT). We evaluated the ability of these indices to predict mortality compared to physiologic results. Additionally, prognostic predictive factors were compared among subgroups with biopsy-proven fibrotic idiopathic interstitial pneumonia (IIP) (biopsy-proven CPFE) and in a separate cohort with subclinical CPFE.
  
  
  METHODS
  Three chest radiologists independently determined FS. EI was automatically quantified. PFTs, smoking history, and composite physiologic index (CPI) were reviewed. Predictors of time to death were determined based on clinico-physiologic factors and CT-based CPFE indices.
  
  
  RESULTS
  The prevalence of biopsy-proven CPFE was 26% (66/254), with an EI of 9.1±7.1 and a FS of 19.3±14.2. In patients with CPFE, median survival and 5-year survival rates were 6.0 years and 34.8%, respectively, whereas those in fibrotic IIP without emphysema were 10.0 years and 60.9% (p = 0.013). However, the extent of fibrosis did not differ significantly between the two cohorts. In subclinical CPFE, prevalence was 0.04% (93/20,372), EI was 11.3±10.4, and FS was 9.1±7.1. FVC and a fibrosis-weighted CT index were independent predictors of survival in the biopsy-proven CPFE cohort, whereas only the fibrosis-weighted CT index was a significant prognostic factor in the subclinical CPFE cohort.
  
  
  CONCLUSIONS
  Recognition and stratification using CT quantification can be utilized as a prognostic predictor. Prognostic factors vary according to fibrosis severity and among cohorts of patients with biopsy-proven and subclinical CPFE.
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Seung Hee
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ho Yun
authors.initials: HY
authors.lastname: Lee
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyung Soo
authors.initials: KS
authors.lastname: Lee
authors.affiliation: The Division of Respiratory and Critical Medicine of the 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: The Division of Respiratory and Critical Medicine of the Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: O Jung
authors.initials: OJ
authors.lastname: Kwon
authors.affiliation: The Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Joungho
authors.initials: J
authors.lastname: Han
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Namkug
authors.initials: N
authors.lastname: Kim
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Joon Beom
authors.initials: JB
authors.lastname: Seo
mesh_terms: D000368:Aged; D001706:Biopsy / Q000379:methods; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000473:pathology; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D011656:Pulmonary Emphysema / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000473:pathology; D011658:Pulmonary Fibrosis / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000473:pathology; D012907:Smoking / Q000009:adverse effects; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods