title: The diagnostic accuracy of pericolonic fat extension and attenuation for colorectal tumors.
abstract: OBJECTIVE
  To evaluate the utility of quantitative analysis of the extension and attenuation of pericolonic fat in the local staging of colorectal cancer (CRC) using multi detector computed tomography (MDCT).
  
  
  METHODS
  This was a retrospective study of 110 patients who were operated due to pathologically proven CRC from January 2007 to January 2010, and who underwent preoperative MDCT of the abdomen and pelvis with administration of intravenous contrast material and image acquisition during the portal venous phase. The mean age was 69 years (range of 38-90 years). Pathological reports were reviewed for TNM staging. All MDCT studies were reviewed by two certified radiologists for maximal and minimal tumor diameter, extent of the infiltrated pericolonic fat (measured in mm), attenuation of the infiltrated pericolonic fat (measured in Hounsfield units), and attenuation of normally appearing fat next to the tumor. The sensitivity and specificity of these parameters in detecting patients with ≥ T3 CRC were calculated.
  
  
  RESULTS
  The overall sensitivity, specificity, and accuracy of pericolonic fat infiltration in detecting patients with ≥T3 stage were 95% (95% CI, 89.0-98.7%), 20% (5.8-43.7%), and 81.9% (74.7-89%) respectively. The mean extent and attenuation of the infiltrated pericolonic fat, in addition to the maximal tumor diameter, were higher in the ≥T3 group (p<0.05). By defining threshold values to these parameters, the positive predictive value for detecting ≥T3 stage tumors approaches 100%.
  
  
  CONCLUSIONS
  Quantitative analysis of pericolonic fat increased the accuracy of MDCT in the detection of local tumor spread in CRC.
authors.affiliation: Department of Radiology, Hillel Yaffe Medical Center, Hadera, Israel; Affiliated with the Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel. Electronic address: raufzeina3@hotmail.com.
authors.forename: Abdel-Rauf
authors.initials: AR
authors.lastname: Zeina
authors.affiliation: Division of Surgery, Hillel Yaffe Medical Center, Hadera, Israel; Affiliated with the Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Mahamid
authors.affiliation: Department of Internal Medicine C, Ha'emek Medical Center, Afula, Israel; Affiliated with the Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Saliba
authors.initials: S
authors.lastname: Walid
authors.affiliation: Department of Radiology, Hillel Yaffe Medical Center, Hadera, Israel; Affiliated with the Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Alicia
authors.initials: A
authors.lastname: Nachtigal
authors.affiliation: Department of Radiology, Hillel Yaffe Medical Center, Hadera, Israel; Affiliated with the Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Mika
authors.initials: M
authors.lastname: Shapira-Rootman
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D015588:Observer Variation; D011169:Portal Vein / Q000000981:diagnostic imaging; D011856:Radiographic Image Enhancement; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media
keywords: Colorectal cancer; Computed tomography; Pericolonic fat density; Pericolonic fat extension; Staging