• Posted October 10, 2024

MS Might Raise a Person's Odds for Cancer

There's a small but significant increased of certain cancers in people battling multiple sclerosis (MS), new research shows.

Those malignancies include cancers of the bladder, brain and cervix, said a team from Rennes University in France.

“People with MS undergo an increased number of tests to monitor MS, making it more likely to detect other diseases,” said study author Emmanuelle Leray. “We found an association between some types of cancer and MS which may have different explanations, depending on a person’s age and the types of cancer."

Leray stressed, however, that "overall, our study found the increased risk of cancer was quite small."

The findings were published Oct. 9 in the journal Neurology.

The study focused on a decade's worth of records from a major French national health care database. Leray's group compared rates of cancer diagnoses in about 141,000 people with MS and almost 563,000 folks without the progressive neurological illness.

Everyone was cancer-free at least three years before the study, and then tracked for an average of eight years. About 40,000 of the study participants developed a cancer during that time.

The study found that people with MS had a 6% increased odds of developing any kind of cancer, compared to folks who didn't have MS. The increased risk was higher for bladder cancers (71% higher odds), brain tumors (68%), and cervical cancers (24%).

That was offset by a 20% lower risk for prostate cancer, a 10% lower odds for colorectal cancer, and a 9% lower risk of breast cancer, the researchers noted.

“The lower risk for colorectal and breast cancers may be due in part to fewer people with MS getting screened for cancer in older age when they may be experiencing more MS symptoms," Leray surmised in a journal news release. "More research is needed, including studies that look at more closely at how cancer screenings may play a role."

The finding on brain cancer risk was also nuanced, he added.

“While our study found a higher risk for brain cancer, it may be due in part to earlier detection in those with MS since they regularly have brain scans which may detect cancers earlier, before a person has symptoms,” Leray explained.

As for the two other tumor types, “Frequent urinary tract infections in people with MS and the use of immunosuppressant drugs may contribute to their higher risk of bladder and cervical cancers," he said.

Because the study was observational in nature, it cannot prove that MS causes or helps prevent cancers, only that certain associations exist.

More information

Find out more about multiple sclerosis at the National Multiple Sclerosis Society.

SOURCE: Neurology, news release, Oct. 9, 2024