Staging of primary colorectal carcinomas with fluorine-18 fluorodeoxyglucose whole-body PET: correlation with histopathologic and CT findings

Radiology. 1998 Mar;206(3):755-60. doi: 10.1148/radiology.206.3.9494497.


Purpose: To evaluate the diagnostic usefulness of positron emission tomography (PET) with fluorine-18 fluorodeoxyglucose (FDG) in patients with primary colorectal carcinomas.

Materials and methods: Forty-eight patients with biopsy-proved (n = 44) or high clinical suspicion for (n = 4) colorectal cancer underwent whole-body PET after intravenous administration of 10 mCi (370 MBq) of FDG. FDG PET results were correlated with computed tomographic (CT), surgical, and histopathologic findings.

Results: PET depicted all known intraluminal carcinomas in 37 patients (including two in situ carcinomas) (sensitivity, 100%), but findings were false-positive in four of seven patients without cancer (three with inflammatory bowel conditions, one who had undergone polypectomy). Specificity was 43% (three of seven patients); positive predictive value, 90% (37 of 41 patients); and negative predictive value, 100% (three of three patients). No FDG accumulation was noted in 35 hyperplastic polyps. FDG PET depicted lymph node metastases in four of 14 patients (sensitivity, 29%). Results were similar to those obtained with CT (true-positive, two of seven patients [sensitivity, 29%]; true-negative, 22 of 26 patients [specificity, 85%]). FDG PET depicted liver metastases in seven of eight patients and was superior to CT, which depicted liver metastases in three patients (sensitivity of 88% and 38%, respectively). FDG PET and CT, respectively, correctly depicted the absence of liver metastases in 35 and 32 patients (specificity, 100% and 97%; negative predictive value, 97% and 86%).

Conclusion: FDG PET has a high sensitivity and specificity for detection of colorectal carcinomas (primary and liver metastases) and appears to be superior to CT in the staging of primary colorectal carcinoma.

MeSH terms

  • Adenocarcinoma / diagnostic imaging*
  • Adenocarcinoma / pathology
  • Adenocarcinoma / secondary
  • Aged
  • Colorectal Neoplasms / diagnostic imaging*
  • Colorectal Neoplasms / pathology
  • Fluorine Radioisotopes*
  • Fluorodeoxyglucose F18*
  • Humans
  • Liver Neoplasms / diagnostic imaging
  • Liver Neoplasms / pathology
  • Liver Neoplasms / secondary
  • Lymphatic Metastasis
  • Male
  • Neoplasm Staging
  • Predictive Value of Tests
  • Sensitivity and Specificity
  • Tomography, Emission-Computed*
  • Tomography, X-Ray Computed


  • Fluorine Radioisotopes
  • Fluorodeoxyglucose F18