title: Tumor heterogeneity and permeability as measured on the CT component of PET/CT predict survival in patients with non-small cell lung cancer.
abstract: OBJECTIVE
  We prospectively examined the role of tumor textural heterogeneity on positron emission tomography/computed tomography (PET/CT) in predicting survival compared with other clinical and imaging parameters in patients with non-small cell lung cancer (NSCLC).
  
  
  METHODS
  The feasibility study consisted of 56 assessed consecutive patients with NSCLC (32 males, 24 females; mean age 67 ± 9.7 years) who underwent combined fluorodeoxyglucose (FDG) PET/CT. The validation study population consisted of 66 prospectively recruited consecutive consenting patients with NSCLC (37 males, 29 females; mean age, 67.5 ± 7.8 years) who successfully underwent combined FDG PET/CT-dynamic contrast-enhanced (DCE) CT. Images were used to derive tumoral PET/CT textural heterogeneity, DCE CT permeability, and FDG uptake (SUVmax). The mean follow-up periods were 22.6 ± 13.3 months and 28.5± 13.2 months for the feasibility and validation studies, respectively. Optimum threshold was determined for clinical stage and each of the above biomarkers (where available) from the feasibility study population. Kaplan-Meier analysis was used to assess the ability of the biomarkers to predict survival in the validation study. Cox regression determined survival factor independence.
  
  
  RESULTS
  Univariate analysis revealed that tumor CT-derived heterogeneity (P < 0.001), PET-derived heterogeneity (P = 0.003), CT-derived permeability (P = 0.002), and stage (P < 0.001) were all significant survival predictors. The thresholds used in this study were derived from a previously conducted feasibility study. Tumor SUVmax did not predict survival. Using multivariable analysis, tumor CT textural heterogeneity (P = 0.021), stage (P = 0.001), and permeability (P < 0.001) were independent survival predictors. These predictors were independent of patient treatment.
  
  
  CONCLUSIONS
  Tumor stage and CT-derived textural heterogeneity were the best predictors of survival in NSCLC. The use of CT-derived textural heterogeneity should assist the management of many patients with NSCLC.
authors: Lister Hospital, Coreys Mills Lane, Stevenage, Hertfordshire, United Kingdom.
authors: Thida
authors: T
authors: Win
authors: Kenneth A
authors: KA
authors: Miles
authors: Sam M
authors: SM
authors: Janes
authors: Balaji
authors: B
authors: Ganeshan
authors: Manu
authors: M
authors: Shastry
authors: Raymondo
authors: R
authors: Endozo
authors: Marie
authors: M
authors: Meagher
authors: Robert I
authors: RI
authors: Shortman
authors: Simon
authors: S
authors: Wan
authors: Irfan
authors: I
authors: Kayani
authors: Peter J
authors: PJ
authors: Ell
authors: Ashley M
authors: AM
authors: Groves
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000401:mortality*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed