Clinical significance of incidental colonic 18F-FDG uptake on PET/CT images in patients with gastric adenocarcinoma

J Gastrointest Surg. 2012 Oct;16(10):1847-53. doi: 10.1007/s11605-012-1941-3. Epub 2012 Jun 30.

Abstract

Background and objectives: We assessed the ability of positron emission tomography-computed tomography (PET/CT) to detect synchronous colonic pathology and determined the significance of 18F-fluorodeoxyglucose (18F-FDG) activity in the colon of gastric cancer patients.

Methods: A total of 239 gastric cancer patients who underwent PET/CT and colonoscopy preoperatively were included. FDG uptake patterns on PET/CT were classified as (1) group A, focal; (2) group B, diffuse; and (3) group C, no uptake. The PET/CT findings were compared with the results of concurrent colonoscopy.

Results: In group A, a total of 123 polyps of >0 mm were observed. Of these, nine polyps were colonic adenocarcinomas and six were high-grade dysplasia. The incidence of colonic adenocarcinomas was significantly higher in group A than in the other two groups (p = 0.037). There was a significant correlation between SUVmax values and incidence of colonic polyps of >10 mm (r = 0.471, p = 0.04). The distribution pattern of SUVmax in polyps with adenoma (>10 mm) was less homogenous than in polyps (>10 mm) with adenocarcinoma.

Conclusions: The focal colonic FDG uptake in PET/CT requires colonoscopic confirmation. The suspicion of colonic malignancy increased in the presence of polyps >10 mm that showed a positive correlation with the SUVmax.

Publication types

  • Evaluation Study

MeSH terms

  • Adenocarcinoma / diagnostic imaging*
  • Adenoma / diagnostic imaging
  • Adenoma / pathology
  • Adult
  • Aged
  • Aged, 80 and over
  • Colon / diagnostic imaging
  • Colon / metabolism
  • Colon / pathology
  • Colonic Neoplasms / diagnostic imaging*
  • Colonic Neoplasms / pathology
  • Colonic Polyps / diagnostic imaging
  • Colonic Polyps / pathology
  • Colonoscopy
  • False Negative Reactions
  • False Positive Reactions
  • Female
  • Fluorodeoxyglucose F18* / pharmacokinetics
  • Humans
  • Incidental Findings
  • Male
  • Middle Aged
  • Multimodal Imaging*
  • Neoplasms, Multiple Primary / diagnostic imaging*
  • Neoplasms, Multiple Primary / pathology
  • Positron-Emission Tomography*
  • Radiopharmaceuticals* / pharmacokinetics
  • Retrospective Studies
  • Stomach Neoplasms / diagnostic imaging*
  • Tissue Distribution
  • Tomography, X-Ray Computed*

Substances

  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18