Follow-up strategies for patients treated for non-metastatic colorectal cancer

It is common clinical practise to follow patients with colorectal cancer (CRC) for several years following their definitive surgery and/or adjuvant therapy. Despite this widespread practice there is considerable controversy about how often patients should be seen, what tests should be performed and whether these varying strategies have any significant impact on patient outcomes.

To review the available evidence concerning the benefits of intensive follow-up of colorectal cancer patients with respect to survival. Secondary endpoints include time to diagnosis of recurrence, quality of life and the harms and costs of surveillance and investigations.

Relevant trials were identified by electronic searches of MEDLINE, EMBASE, CINAHL, CANCERLIT, Cochrane Controlled Trials Register, Science Citation Index, conference proceedings, trial registers, reference lists and contact with experts in the field.

Only randomised controlled trials comparing different follow-up strategies for patients with non-metastatic CRC treated with curative intent were included.

Trial eligibility and methodological quality were assessed independently by the three reviewers.

Five trials were included. There was evidence that an overall survival benefit at 5 years exists for patients undergoing more intensive follow-up (OR = 0.67, 95% confidence interval 0.53 - 0.84; RD = -0.07, CI -0.12 - -0.02). The absolute number of recurrences was similar (OR = 0.91; 95% confidence interval 0.72 - 1.14; RD = 0.00, CI -0.07 - 0.07) and although the weighted mean difference for the time to recurrence was significantly reduced by 6.75 (95% confidence interval -11.06 - -2.44) there was significant heterogeneity between the studies. Analyses demonstrated a mortality benefit for performing more tests versus fewer tests (OR = 0.66; 95% confidence interval 0.46 - 0.95) and liver imaging versus no liver imaging (OR = 0.66; 95% confidence interval 0.46 - 0.95). However when both these results are expressed as a risk difference this significance is lost (RD = -0.06; CI -0.25 - 0.13). No useful data on quality of life, harms or cost-effectiveness were available for further analysis.

The results of our review suggest that there is an overall survival benefit for intensifying the follow-up of patients after curative surgery for colorectal cancer. Because of the wide variation in the follow-up programmes used in the included studies it is not possible to infer from the data the best combination and frequency of clinic (or family practice) visits, blood tests, endoscopic procedures and radiological investigations to maximise the outcomes for these patients. Nor is it possible to estimate the potential harms or costs of intensifying follow-up for these patients in order to adopt a cost-effective approach in this clinical area. Large clinical trials underway or about to commence are likely to contribute valuable further information to clarify these areas of clinical uncertainty.