A new study finds that only a tiny proportion of Canadians who should be screened for colorectal cancer are receiving the test that could detect the disease that is the second leading cause of cancer-related deaths in Canada.
The study, published in the Canadian Medical Association Journal, looked at the frequency of colorectal cancer screening in four Canadian provinces: British Columbia, Saskatchewan, Ontario, and Newfoundland and Labrador.
Dr. Ryan Zarychanski and colleagues wanted to know whether regular contact with a family doctor increased the likelihood that a patient would receive the screening. The study included 12,776 men and women aged 50 years or older who were at average risk for colorectal cancer.
The researchers found only about 23.5 per cent of eligible people reported any history of colorectal cancer screening. That dropped to 17.6 per cent, however, when only up-to-date screening was considered.
People who reported increased contact with a family doctor during the study period were more likely to report up-to-date colorectal cancer screening. But, even among those who reported more than four doctor visits in the 12 months before the survey, only one-fifth reported up-to-date colorectal cancer screening.
Fewer women than men, and fewer non-white than white respondents reported receiving colorectal cancer screening.
"Despite the high incidence and mortality associated with colorectal cancer and the known survival benefits associated with population screening, colorectal cancer screening remains inadequate," the authors write.
According to the recommendations from the Canadian Task Force on Preventive Health Care, people at average risk, who are 50 years of age or older, should have an annual or biannual fecal occult blood test or should undergo periodic sigmoidoscopy, a test that lets a physician look at the inside of the large intestine from the rectum through the last part of the colon, called the sigmoid.
In the lead editorial, Drs. Alan Barkun and Ken Flegel argue that physicians must take a more active role in promoting colorectal cancer screening. They also argue for a national colorectal screening program strategy.
"At present, the most common reason for not undergoing screening is that it was not recommended by the treating physician," they write.
"Until there is an active national program, individual physicians must take the lead. Although several professional societies and foundations are poised and willing to help, physicians must first address their own ignorance and reticence and accept their duty to begin informing and persuading their patients to be screened."
Colorectal cancer is the second leading cause of cancer-related deaths in Canada. In 2007, about 20,460 new cases of colorectal cancer will be diagnosed and about 8,700 people will die from this disease.
The good news is that, unlike many other cancers, colon cancer is easy to detect in its early stage, when it is most often pre-malignant. And if detected early, the mortality is low, with 90 per cent of patients surviving five years.
