Utility of computed tomography and 18 F-fluorodeoxyglucose with positron emission tomography/computed tomography for distinguishing appendiceal mucocele caused by mucinous adenocarcinoma from other pathologies

Colorectal Dis. 2020 Dec;22(12):1984-1990. doi: 10.1111/codi.15308. Epub 2020 Sep 7.


Aim: Differentiating appendiceal mucocele with mucinous adenocarcinoma from other pathologies before surgery is difficult. The objective of this study was to evaluate the utility of CT and 18 F-fluorodeoxyglucose (FDG) with positron emission tomography (PET)/CT for differentiating mucinous adenocarcinoma of appendiceal mucocele from other pathologies.

Method: The study included 25 patients who underwent surgery for clinically diagnosed appendiceal mucoceles detected on CT at the University of Tokyo Hospital. Among these patients, 19 underwent FDG-PET/CT preoperatively. We compared features of the CT imaging findings and maximum standard uptake values (SUVmax ) detected by FDG-PET/CT between mucocele with mucinous adenocarcinoma and other pathologies.

Results: A total of 13 men (52%) and 12 women (48%) were included in this study, with a median age of 65 years (range 34-83). There were six patients (24%) with pathologically confirmed mucinous adenocarcinoma, 15 patients (60%) with appendiceal mucinous neoplasm and four patients (16%) with simple mucocele caused by chronic inflammation. On the CT findings, wall irregularity was the only significant feature for the two groups in this study (83.3% vs 0.0%, P < 0.01). There was a significant difference in the SUVmax levels on PET/CT between the two groups (100.0% vs 20.0%, P < 0.01).

Conclusion: Distinguishing between mucocele with mucinous adenocarcinoma and other pathologies using imaging modalities is challenging. Our results suggest that wall irregularity on CT and elevated SUVmax on PET/CT are useful factors that can be employed for such discrimination.

Keywords: FDG-PET/CT; appendiceal mucocele; mucinous adenocarcinoma; mucinous appendiceal neoplasm.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma, Mucinous* / diagnostic imaging
  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Fluorodeoxyglucose F18
  • Humans
  • Male
  • Middle Aged
  • Mucocele* / diagnostic imaging
  • Positron Emission Tomography Computed Tomography
  • Positron-Emission Tomography
  • Radiopharmaceuticals
  • Tomography, X-Ray Computed


  • Radiopharmaceuticals
  • Fluorodeoxyglucose F18