A new study has found that some cancers occur slightly more frequently in people with multiple sclerosis (MS) than in people without MS. The study will be published online in the October 9, 2024 issue of Neurology®, the medical journal of the American Academy of Neurology. Cancer types found to have a small increased risk include bladder cancer, brain cancer, and cervical cancer. This study does not prove that MS increases the risk of cancer. Just show the relevance.
In MS, the body’s immune system attacks myelin, a fatty white substance that insulates and protects nerves. MS can be chronic, unpredictable, and disabling.
People with MS undergo an increased number of tests to monitor their MS, and other diseases are more likely to be detected. We found a link between some types of cancer and MS, but this may have different explanations depending on a person’s age and the type of cancer. Overall, our study found that the increased risk of cancer was very small. ”
Dr. Emmanuel Leray, study author, University of Rennes, France
For the study, researchers looked at 10 years of data from France’s national health database. Researchers identified 140,649 people with MS and matched them to 562,596 people without MS on factors such as age, gender, and place of residence. All participants were cancer-free in the 3 years before the study. They were followed for an average of 8 years.
During the study period, 8,368 people with MS and 31,796 people without MS developed cancer.
Researchers determined that 799 cancers occur per 100,000 person-years in people with MS and 736 cancers per 100,000 person-years in people without MS. Person-years represent both the number of people who participated in the study and the time each person spent in the study.
Researchers found that people with MS had a 6% higher risk of developing any type of cancer, regardless of age, gender, or place of residence. They also found that the risk of cancer was higher for those under 55 and lower for those over 65 when compared to people without MS.
Next, the researchers looked at the type of cancer. MS patients had a 71% increased risk of bladder cancer, a 68% increased risk of brain cancer, and a 24% increased risk of cervical cancer. However, they had a 20% lower risk of prostate cancer, a 10% lower risk of colorectal cancer, and a 9% lower risk of breast cancer.
“While our study found an increased risk of brain tumors, MS patients regularly undergo brain scans, which may detect cancer early, before symptoms appear, so MS patients early detection may be a contributing factor,” Leray said. “Frequent urinary tract infections and the use of immunosuppressants in patients with multiple sclerosis may contribute to an increased risk of bladder and cervical cancer.”
Professor Leray said: “The lower risk of colorectal and breast cancer may also be due to fewer people with MS being screened for cancer at older ages, when symptoms of MS are more common. “Further research is needed, including studies that look more closely.” What role can cancer screening play? ”
A limitation of the study was that information such as education, income, smoking, and alcohol consumption was not available from national databases, so researchers were unable to control for these factors.
This study was supported by the Rennes Institute of Clinical Neuroscience and the EDMUS-ARSEP Foundation.
sauce:
American Academy of Neurology
Reference magazines:
Pierret, C., et al. (2024) Cancer risk in patients with multiple sclerosis: a 10-year national retrospective cohort study. Neurology. doi.org/10.1212/WNL.0000000000209885.
