title: Fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography for the detection of proximal synchronous lesions in patients with obstructive colorectal cancer.
abstract: OBJECTIVE
  We aimed to investigate the ability of fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) to detect synchronous neoplasms, specifically obstructive colorectal cancer (CRC) and CRC in the proximal colon and to suggest a management strategy based on FDG PET/CT findings.
  
  
  METHODS
  From the CRC surgery database of our institution, 518 patients with obstructive CRC whose proximal colon could not be examined by colonoscopy and who underwent preoperative FDG PET/CT were eligible for this study. Of these, final analyses were performed in 345 patients who had reference standards for the proximal colon, which were a surgical colectomy specimen and/or postsurgical colonoscopy. The per-patient and per-lesion performances of FDG PET/CT for synchronous CRC diagnosis were determined.
  
  
  RESULTS
  Of 345 patients, 14 (4.1%) had 14 proximal synchronous CRCs. Thirty-four patients showed 39 areas of abnormal FDG uptake on PET/CT in the colon proximal to the obstructive CRC. PET/CT detected all of the 14 proximal synchronous CRCs. The per-patient PET/CT sensitivity, specificity, positive predictive value, and negative predictive value for proximal synchronous CRC were 100%, 93.9%, 41.2%, and 100%, respectively. Per-lesion values were 100%, 92.6%, 35.9%, and 100%, respectively. The per-lesion sensitivity and negative predictive value of PET/CT for advanced adenoma were 45.5% and 92.7%, respectively.
  
  
  CONCLUSIONS
  The FDG PET/CT shows a high sensitivity and negative predictive value for the detection of proximal synchronous CRC in patients with obstructive CRC, enabling negative findings in the proximal colon on PET/CT to definitively exclude proximal synchronous CRC. Preoperative PET/CT recommended to determine the proper surgical plan in patients with obstructive CRC.
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Wan Soo
authors.initials: WS
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Hyo Sang
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jeong-Mi
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Min Seob
authors.initials: MS
authors.lastname: Kwak
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sung Wook
authors.initials: SW
authors.lastname: Hwang
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Sang Hyoung
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Dong-Hoon
authors.initials: DH
authors.lastname: Yang
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Kyung-Jo
authors.initials: KJ
authors.lastname: Kim
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Myung
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Suk-Kyun
authors.initials: SK
authors.lastname: Yang
authors.affiliation: Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Byeon
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging* / Q000601:surgery; D000368:Aged; D003082:Colectomy; D003106:Colon / Q000000981:diagnostic imaging*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007415:Intestinal Obstruction / Q000000981:diagnostic imaging* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: computed tomography; positron emission tomography; synchronous colorectal cancer