title: Three-dimensional positron emission tomography image texture analysis of esophageal squamous cell carcinoma:  relationship between tumor 18F-fluorodeoxyglucose uptake heterogeneity, maximum standardized uptake value, and tumor stage.
abstract: OBJECTIVE
  To explore the relationship of a new PET image parameter, (18)F-fluorodeoxyglucose ((18)F-FDG) uptake heterogeneity assessed by texture analysis, with maximum standardized uptake value (SUV(max)) and tumor TNM staging.
  
  
  METHODS
  Forty consecutive patients with esophageal squamous cell carcinoma were enrolled. All patients underwent whole-body preoperative (18)F-FDG PET/CT. Heterogeneity of intratumoral (18)F-FDG uptake was assessed on the basis of the textural features (entropy and energy) of the three-dimensional images using MATLAB software. The correlations between the textural parameters and SUV(max), histological grade, tumor location, and TNM stage were analyzed.
  
  
  RESULTS
  Tumors with higher SUV(max) were seen to be more heterogenous on (18)F-FDG uptake. Significant correlations were observed between T stage and SUV(max) (r(s)=0.390, P=0.013), entropy (rs=0.693, P<0.001), and energy (r(s)=-0.469, P=0.002). Correlations were also found between SUV(max), entropy, energy, and N stage (r(s)=0.326, P=0.04; r(s)=0.501, P=0.001; r(s)=-0.413, P=0.008). The American Joint Committee on Cancer stage correlated significantly with all metabolic parameters. The receiver-operating characteristic curve demonstrated an entropy of 4.699 as the optimal cutoff point for detecting tumors above stage II(b) with an areas under the ROC curve of 0.789 (P<0.001).
  
  
  CONCLUSIONS
  This study provides initial evidence for the relationship between the new parameter of tumor uptake heterogeneity and the commonly used simplistic parameter of SUV and tumor stage. Our findings suggest a complementary role of these parameters in the staging and prognosis of esophageal squamous cell carcinoma.
authors.affiliation: Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong, China.
authors.forename: Xinzhe
authors.initials: X
authors.lastname: Dong
authors.forename: Ligang
authors.initials: L
authors.lastname: Xing
authors.forename: Peipei
authors.initials: P
authors.lastname: Wu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Fu
authors.forename: Honglin
authors.initials: H
authors.lastname: Wan
authors.forename: Dengwang
authors.initials: D
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Yin
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Sun
authors.forename: Jinming
authors.initials: J
authors.lastname: Yu
mesh_terms: D000328:Adult; D000368:Aged; D001692:Biological Transport; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000473:pathology; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism*; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D019788:Fluorodeoxyglucose F18