Surveillance after colorectal cancer resection: a systematic review

Background Surveillance programs are widely accepted as an integral part of the treatment plan provided to patients after surgical treatment of colorectal cancer. Despite an enormous amount of research performed regarding these programs, there is still uncertainty regarding what is appropriate surveillance. Objective We sought to systematically review recent literature regarding outcomes achieved with different types of surveillance programs for patients with surgically treated colorectal cancer. Data sources A search of the PubMed database was performed to identify studies published in the English language between January 2000 and January 2010. Study selection We included 2 types of studies in our systematic review: first, comparative studies where 2 or more surveillance strategies were applied and outcomes compared; second, single-cohort studies where the outcomes of a single surveillance strategy were reported. Main outcome measures Cancer-related outcomes included survival, recurrence detection rate, and the ability of a recurrence to be resected with curative intent. Results Our review found 15 studies meeting our inclusion criteria. Of these, 9 were comparative (4 randomized trials) and 6 were single-cohort studies. One study reported a better survival rate among patients who received more intensive follow-up. The vast majority of recurrences occurred within 3 years. Limitations Our review found that the recent literature regarding the efficacy of surveillance is inconclusive, largely because of the small sample sizes and the heterogeneity in the surveillance programs and outcomes reported. Conclusions Future randomized trials need to focus on larger sample sizes, and experimental designs should isolate specific elements of surveillance to better understand how each element contributes to improvements in patient outcomes. Risk stratification and duration of surveillance are key elements of surveillance strategies that also deserve focused investigation.