Incidental focal colonic lesions found on ¹⁸Fluorodeoxyglucose positron emission tomography/computed tomography scan: further support for a national guideline on definitive management

Abstract

Incidental abnormal colonic uptake of (18)FDG, determined by a PET/CT scan requires definitive colonic investigation in patients suitable for further treatment because significant colonic pathology is frequently identified. The benefit of this approach should be discussed in specialist MDT meetings and tailored to each patient; however, national guidelines for management are required.

Diagnostic accuracy of 18F-FDG PET/CT for detection of advanced colorectal adenoma

“…1,6,7,14,17 However, the present authors and others have shown the ability of PET to detect smaller adenomas, possibly due to more advanced histology (e.g., villous component or highgrade dysplasia) possibly due to greater metabolic activity. 9,12,14,22 Others report incidental detection of adenomas as small as 3e5 mm with high-grade dysplasia. 12 The present data once again challenge the concept that size is the only variable explaining adenoma detection.…”

“…9,12,14,22 Others report incidental detection of adenomas as small as 3e5 mm with high-grade dysplasia. 12 The present data once again challenge the concept that size is the only variable explaining adenoma detection. In another well-performed, large study, Ravizza et al 22 found by multiand univariate analyses that a villous component and highgrade dysplasia were independently associated with PET positivity.…”

“…9,10 In general, larger adenomas and cancers are better detected, and it is generally agreed upon that despite the risk of false positives, focal colonic FDG-PET avid foci should be further pursued with colonoscopy given the potential for an adenoma or cancer to be present. 11,12 What is not known is whether an individual who has had a negative combined PET/CT examination can be considered free of worrisome lesions, specifically advanced neoplasia (advanced adenoma and adenocarcinoma). Prior retrospective studies of combined PET and standard CT mainly included cases both with and without colonoscopic followup such that a comprehensive assessment of all incidental colonic findings at PET in these patients was not reported on for a variety of reasons.…”

Timely investigation of incidental focal colorectal fluorodeoxyglucose uptake

“…We congratulate Farquharson et al. [1] for presenting an interesting and well‐designed study with a thoughtful discussion. A large volume of work has been required in following up a cohort incidentally found to have focal colorectal fluorodeoxyglucose (FDG) uptake in the course of undergoing positron emission tomography/computed tomography (PET/CT).…”

“…The suggestion of guidelines for this situation seems excessive, however. After all, these cases are uncommon (24 in a single‐centre study over 26 months [1], equating to approximately one case per month). It would be a grave indictment of oncologists that they cannot provide adequate follow‐up for these particular cases.…”