Evidence-based guideline recommendations on the use of positron emission tomography imaging in colorectal cancer

Aims: To provide evidence-based practice guideline recommendations on the use of fluoro-2-deoxy-d-glucose positron emission tomography (PET) for diagnosis, staging, assessing treatment response, liver metastasis and restaging or recurrence of colorectal cancer.

Materials and methods: A systematic review by Facey et al. (Health Technology Assessment 2007;11(44):iii-iv, xi-267) was used as the evidence base for recommendation development. As the review was limited to August 2005, the evidence base was updated to May 2010 using the same search strategies for MEDLINE and EMBASE used in the original review. The authors of the current systematic review drafted recommendations, which were reviewed, adapted and accepted by consensus by the Ontario provincial Gastrointestinal Disease Site Group and a special meeting of clinical experts.

Results: The results from the Facey et al. review for colorectal cancer included three other systematic reviews and 24 primary studies. The 2005 to 2010 updated search included 10 additional systematic reviews and 28 primary studies. Recommendations were developed based on this evidence and accepted by consensus.

Conclusions: The routine use of PET is not recommended for the diagnosis or staging of clinical stage I-III colorectal cancers. PET is recommended for determining management and prognosis if conventional imaging is equivocal for the presence of metastatic disease. PET is also not recommended for routine surveillance in patients with colorectal cancer treated with curative surgery at high risk for recurrence. It is recommended to determine the site of recurrence in the setting of rising CEA when conventional work-up fails to unequivocally identify metastatic disease. Finally, PET is recommended in the preoperative assessment of colorectal cancer liver metastasis before surgical resection.