Utility of CT colonography and/or PET-CT preoperatively in obstructing left-sided colorectal cancers - a systematic review

Jennifer McGarry, Zi Qin Ng, Fintan Ryan, Mary Theophilus

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Purpose15-20% of patients present with near obstructing left-sided colorectal cancer. CT colonography (CTC) or PET-CT has been used to detect synchronous lesions, which may alter preoperative planning of colonic resection. We aim to synthesize the usefulness of CT colonography and/or PET-CT in detecting synchronous proximal colon carcinomas in patients who have undergone an incomplete colonoscopy due to a stenosing or obstructing distal colorectal cancer. MethodologyA systematic review was performed by searching the databases up to December 2021. Data collected included demographics of the study population, rate of detection of synchronous carcinomas and impact on management of detection of synchronous carcinomas. ResultsA total of 22 studies were included: 17 studies focused on CTC, 3 on PET-CT, and 2 integrated PET-CT with CTC; 2855 patients were included; 53% of patients were male, and 47% were female. All studies reported detection of synchronous proximal colorectal carcinomas using CTC, PET-CT or CTC, and PET-CT combined. CTC detected synchronous carcinomas in 0.2-12.2% of patients. PET-CT was useful in detecting synchronous carcinomas in 4.05-23% of patients. Integrated PET-CT and CTC detected synchronous carcinomas in 2-15% of patients. The surgical plan was changed in 2.4-14.3% of patients after the use of CTC. One PET-CT study reported a change in management in 13.5%. No complication was reported by the use of CTC. ConclusionCTC is an effective and useful adjunct to colonoscopy in assessing the proximal colon when colonoscopy fails to do so. However, more evidence is needed with the use of PET-CT for this patient population.
Original languageEnglish
Pages (from-to)1487-1494
Number of pages8
JournalANZ Journal of Surgery
Issue number6
Early online date6 Apr 2023
Publication statusPublished - Jun 2023
Externally publishedYes

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