title: Which FDG/PET parameters of the primary tumors in colon or sigmoid cancer provide the best correlation with the pathological findings?
abstract: BACKGROUND
  To compare (18)F-fluoro-2-deoxdeoxyglucose (FDG) positron emission tomography (PET) related parameters of primary colon or sigmoid cancer (CSC) with pathological findings.
  
  
  METHODS
  Seventy-seven CSC patients who have undergone preoperative PET computed tomograms (PET/CT) are included in this study. Maximum PET-based tumor length (TL) and tumor width (TW) are determined using several auto-segmentation methods, and various thresholds of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are measured. The PET-based TL and TW are compared with maximum pathological length and width on the pathological specimen.
  
  
  RESULTS
  Using a 30% threshold level for maximum uptake of TL (TL30%) and TW (TW30%) yield results that provide an optimal match with maximum pathological length (R=0.81, p<0.001) and width (R=0.70, p<0.001). TW30% was an independent factor for predicting pathological T3 or T4 stages (OR=1.26, 95% CI=1.07-1.47, p=0.01). The receiver-operating characteristic curves show MTV at a fixed threshold of 40% maximum uptake (MTV40%), and TW30% achieved better correlation with the advanced pathological T stage. No associations with positive N stage were observed.
  
  
  CONCLUSIONS
  Pretreatment PET/CT is a useful tool for predicting the final pathological findings for CSC patients requiring surgical procedures.
authors.affiliation: Department of Radiation Oncology, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404, Taiwan. vincent1680616@yahoo.com.tw
authors.forename: Shang-Wen
authors.initials: SW
authors.lastname: Chen
authors.forename: William Tzu-Liang
authors.initials: WT
authors.lastname: Chen
authors.forename: Yi-Chen
authors.initials: YC
authors.lastname: Wu
authors.forename: Kuo-Yang
authors.initials: KY
authors.lastname: Yen
authors.forename: Te-Chun
authors.initials: TC
authors.lastname: Hsieh
authors.forename: Tze-Yi
authors.initials: TY
authors.lastname: Lin
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Kao
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001706:Biopsy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D047368:Tumor Burden
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Automatic contours; Colon cancer; PET/CT; Pathology correlation