Provincial health authorities have once again discovered a problem with a laboratory test designed for people considered at average risk of colon cancer.
B.C. Laboratories and B.C. Cancer Agency say recent fecal immunochemical test (FIT) results are showing a spike in the number of positive screens being returned — more patients are testing positive than is typical.
On average, 15 per cent of patients screen positive and require further testing, but the Provincial Health Authority says an additional five per cent of patients who would have previously had a borderline negative result can expect to screen positive.
“We are working diligently with our partners on a long-term resolution that will ensure British Columbians are able to continue to have trust and confidence in this very important early cancer screening tool,” said Dr. Jim Cupples, vice president of the B.C. Agency for Pathology and Laboratory Medicine. “We are working with our partners including B.C. Cancer and the Ministry of Health to resolve the issue as quickly as possible.”
A spike in positive tests last October led to the B.C. Cancer Agency suspending all stool sample collection testing for three months.
The test sensitivity problem was blamed on a liquid solution, known as a reagent, used to test the fecal samples in the labs. A new reagent, which has been in use since mid-December, was performing to expected standards until very recently.
The Provincial Health Services Authority says, despite the recent spike, testing will continue and a higher percentage of patients than normal will be referred for a follow-up colonoscopy.
“We recognize that a testing suspension like we experienced in the fall, although temporary, may have caused concern or confusion for patients waiting for test results, or who recently received a referral for a FIT,” said Dr. John Spinelli, the vice-president of population oncology at B.C. Cancer.
The Colon Screening Program recommends all patients with abnormal FIT results have a follow-up colonoscopy.