Published in the journal of the American Medical Association, the study showed that both a standard CT scan and a blood test for a tumour marker known as CEA (carcinoembryonic antigen) improved doctors’ chances of detecting and removing a recurrence of colorectal cancer.
Study participants who underwent either of the tests were two to three times more likely to undergo another surgery that rid them of a recurring cancer, compared to colorectal cancer patients who did not receive follow-up screening after their initial surgery.
John Primrose, Professor of Surgery at the University of Southampton who led the study, comments: “This study gives us, for the first time, unequivocal evidence of the benefits of following up patients who have had surgery for colorectal cancer. We also now know that even patients with early stage bowel cancer benefit from follow-up too.”
Colorectal cancer is the third most common cancer worldwide, with 1.24 million cases reported to the International Agency for Research on Cancer in 2008.
Traditionally in current practice, patients who have had curative surgery for colorectal cancer undergo regular follow-up for at least five years to detect recurrence. However, this is a common practice which to date has been based on limited evidence, Professor Primrose says. Furthermore, the evidence for whether to follow-up patients with very early stage bowel cancer following surgery was particularly unclear.
During the study, more than 1,200 patients from 39 hospitals in England were split into one of four groups. The first group received minimal follow-up screening after surgery, the second received CT scans only, the third received CEA blood testing only and the fourth received both CEA testing and CT scans.
About 2.3 per cent of the patients in the minimum follow-up group received a second surgery to remove the recurring colorectal cancer. By comparison, 6.7 per cent of the CEA group and eight per cent of the CT group received another surgery to treat a cancer recurrence.
People who received both CEA testing and a CT scan did not have any advantage in cancer detection over those who underwent CT or CEA testing alone.
Professor Primrose adds: “The fact that there’s no apparent advantage in having both tests means that follow-up appointments can become more economical. CEA testing has the advantage that it can be done by the GP, thereby avoiding hospital visits, and has no radiation dose.”
Notes for editors
The study was funded by the National Institute for Health Research Heath Technology Assessment programme.