Evidence-based follow-up in colorectal cancer—quo vadis?

Colorectal cancer is the third most common and the third most lethal cancer disease in the western world. As most patients undergo treatment with curative intent at initial diagnosis, postoperative surveillance protocols have been established with the primary aim to detect possible disease recurrence in an early resectable stage. Various international guidelines recommend an intensive surveillance protocol over a 5-year time period. These guidelines are based on the reported significant benefit regarding overall patient survival, and on the observation that 90% of recurrences occur within the first 5 years following resection. Surveillance protocols include regular clinical examinations, measurement of the carcinoembryonic antigen, computed tomography scans and regular endoscopies. While there is plenty of evidence regarding the scheduling of endoscopies, the frequency of carcinoembryonic antigen measurements and computed tomography scans has been ever since under debate. The benefit of intensive compared to low frequency surveillance protocols regarding disease-specific survival has never been shown. Moreover, recent meta-analyses and randomized controlled trials challenge current guidelines. Intensive carcinoembryonic antigen assessment and computed tomography scan follow-up protocols seem to fail in generating better overall and disease-specific survival in colorectal cancer patients compared to less intensive surveillance strategies. This change over the last few decades parallels the treatment evolution of colorectal cancer from a primarily surgical to a multidisciplinary task. Instead of advocating a reduction of the follow-up intensity, these findings should stimulate the colorectal oncology field to move from a one-fits-all to a patient-centered surveillance.