CME or traditional surgery for right-sided colon cancer?

One of the big controversies in colorectal cancer research is whether complete mesocolic excision (CME) offers a benefit for patients with carcinoma of the right colon or whether it might even harm these patients. A randomized trial to clarify this question has often been advocated. However, setting up such a trial is hampered by a major problem, which is mainly related to the difficulty of defining a standardized control group. First, there is no consensus of a standard non-CME hemicolectomy. Second, a surgeon who has been trained for CME will perform a “standard” right hemicolectomy differently than before. It won’t be the traditional hemicolectomy but a 5/6 CME-hemicolectomy, thus making it very difficult to detect a difference. Our approach to answering the question was a multicenter, non-randomized, registry-based trial with centralized assessment of the entire specimen. This trial has just closed recruitment after enrolling more than 1000 patients, so that long-term results can be expected in a few years.