|LETTER TO EDITOR
|Year : 2015 | Volume
| Issue : 3 | Page : 225
Segmental Considerations in Colonoscopy Recommendations for Investigating Focal Colonic FDG Activity on PET/CT
Joseph C Lee1, Gemma F Hartnett2, Aravind S Ravi Kumar3
1 Department of Medical Imaging, The Prince Charles Hospital, Chermside, Herston, Queensland; School of Medicine, University of Queensland, Herston, Queensland, Australia
2 Department of Medical Oncology, Redcliffe General Hospital, Redcliffe, Queensland, Australia
3 Department of Nuclear Medicine and Specialised PET Services, Royal Brisbane and Women's Hospital, Herston, Queensland, Australia
|Date of Web Publication||20-Aug-2015|
Dr. Joseph C Lee
Department of Medical Imaging, The Prince Charles Hospital, Chermside, Queensland 4006
|How to cite this article:|
Lee JC, Hartnett GF, Ravi Kumar AS. Segmental Considerations in Colonoscopy Recommendations for Investigating Focal Colonic FDG Activity on PET/CT. World J Nucl Med 2015;14:225
|How to cite this URL:|
Lee JC, Hartnett GF, Ravi Kumar AS. Segmental Considerations in Colonoscopy Recommendations for Investigating Focal Colonic FDG Activity on PET/CT. World J Nucl Med [serial online] 2015 [cited 2019 May 24];14:225. Available from: http://www.wjnm.org/text.asp?2015/14/3/225/161725
We applaud the efforts of Liu et al. in attempting to make recommendations for specific patients who should undergo colonoscopy following the finding of unexpected colorectal incidentalomas (CIs) avid for fluorodeoxyglucose (FDG) on positron emission tomography with computed tomography (PET/CT). In the largest meta-analysis to date  involving almost 90,000 patients, it was concluded that colonoscopy is warranted for all CIs. However, the required time and costs of this recommendation would be huge. Hence, the attempt to prioritize certain patients within a population is commendable. After all, an additional malignant (or premalignant) diagnosis may significantly impact prognosis and treatment.
In addition to the specific PET/CT population of interest identified by Liu et al.,  we wonder if the selection of patients would be further refined by two factors. First, the statistics are more likely to be meaningful in a population of patients who underwent PET/CT for a clinical indication and then colonoscopy for follow-up incidental findings. Simply matching patients who underwent both investigations would inevitably skew the pretest probabilities of significant findings.
Second, the precise colonic segment of interest is important. We certainly benefited from both these factors being central to our own work,  finding that proximal colon lesions had a much higher positive predictive value (PPV) for clinically significant lesions (such as malignancies and premalignancies). It was unclear if anatomical location was considered or if whole colon analysis was done in the cases. Whole colon analysis may be difficult to interpret as there remains an uncertainty about the PPV being 100% (i.e., we cannot be sure that the FDG-avid lesion is actually the cancer rather than something else). In short, could segmental analysis further allay concerns about the indiscriminate use of colonoscopy for this purpose?
| References|| |
Liu T, Behr S, Khan S, Osterhoff R, Aparici CM. Focal colonic FDG activity with PET/CT: Guidelines for recommendation of colonoscopy. World J Nucl Med 2015;14:25-30.
Treglia G, Taralli S, Salsano M, Muoio B, Sadeghi R, Giovanella L. Prevalence and malignancy risk of focal colorectal incidental uptake detected by (18) F-FDG-PET or PET/CT: A meta-analysis. Radiol Oncol 2014;48:99-104.
Lee JC, Hartnett GF, Hughes BG, Ravi Kumar AS. The segmental distribution and clinical significance of colorectal fluorodeoxyglucose uptake incidentally detected on PET-CT. Nucl Med Commun 2009;30:333-7.