June 6, 2022

Cancer Screening and Diagnosis in People with MS in Canada

Early detection of cancer is critical for improved survival. A recent Canadian study finds that breast and colorectal cancer were less likely to be detected through regular cancer screening in people living with MS. Reduced participation in screening might be due to higher rates of disability in people with MS, limitations to access, or competing demands of managing MS.

While risk of cancer is not higher in people living with MS, Dr. Ruth Ann Marrie and team previously reported lower breast and colorectal cancer survival rates in people living with MS in Manitoba and Ontario, Canada. In this most recent study, Dr. Ruth Ann Marrie and team examined whether cancer screening and timely diagnosis affect cancer survival in people living with MS.

  • Using health administrative data, the research team examined breast cancer cases between 2007-2015 and colorectal cancers between 2009-2012 in people with MS in Ontario.
  • They examined a total of 351 people with MS and breast cancer along with 1,404 matched controls without MS, and 54 patients with MS and colorectal cancer and 216 matched controls without MS.

From this data, they found that fewer cases of breast cancer were detected and possibly colorectal cancer through regular cancer screening services such as mammograms and colonoscopies. However, MS was not associated with differences in breast cancer stage at diagnosis, and there were no differences in length of time to diagnosis. Additionally, colon cancer was more likely to be detected at an earlier stage in people with MS. The researchers identified that 21.2% of people with MS and breast cancer and 33.3% of the patients with MS and colorectal cancer as having a disability based on need for home care services and long-term care, but were not able to capture other disabilities based on the available data, suggesting that higher rates of disability may be a factor in reducing routine cancer screening.

Understanding how people living with MS are interacting with the health system for regular cancer screening and identifying the barriers that may prevent them from accessing these services, is important to improve preventative care and cancer-related outcomes. If you are living with MS, please speak to your healthcare team about routine cancer screening.

For more information about the research, click here.


Article published in Neurology - Multiple Sclerosis and the Cancer Diagnosis. Diagnostic Route, Cancer Stage, and the Diagnostic Interval in Breast and Colorectal Cancer. Link to article - here