Vancouver – BC Laboratories and BC Cancer have identified an issue with the test used to screen for colon cancer.
Recent fecal immunochemical test (FIT) results are showing an increase in the number of positive screens being returned—more patients are testing positive than is typical. This higher rate was detected by the improved monitoring put in place last year following a similar issue.
“Lab providers and BC Cancer’s Colon Screening Program have recently noticed an increase in the percentage of positive screens, which suggests that some borderline negative results are now testing positive,” said Dr. Jim Cupples, the vice president, medical for the BC Agency for Pathology and Laboratory Medicine, a clinical division of BC Clinical and Support Services Society. “We are working with our partners including BC Cancer and the Ministry of Health to resolve the issue as quickly as possible.”
The issue has been identified as a problem with the liquid solution, known as a reagent, used to test the fecal samples in the labs. A new reagent has been in use since mid-December 2017, when testing resumed after a three-month suspension due to similar issues. The new reagent was performing to expected standards until very recently.
Testing will continue; however, physicians and patients are being informed that there will be a higher percentage of patients than normal who are referred for follow-up colonoscopy. The Colon Screening Program recommends all patients with abnormal FIT results have a follow-up colonoscopy.
A positive FIT result is common and does not mean that the patient has cancer. On average, 15 per cent of patients screen positive and require further testing. It is expected that an additional five per cent of patients will now screen positive, whereas previously, they would have had a borderline negative result.
BC Laboratories, BC Cancer and the Ministry of Health are actively exploring all options to address this situation as quickly as possible.