A new study from Karolinska Institutet shows that people with multiple sclerosis (MS) may be at a lower risk for cancer overall, but at a higher risk of developing certain types of cancer, such as brain tumors and bladder cancer. The study is published in the latest print issue of Neurology , the medical journal of the American Academy of Neurology.
Researchers looked at the medical records of 20,000 people with MS and 204,000 people without the diagnosis. After 35 years, they found that the people with MS had a decreased overall risk of cancer by 10 percent compared to people who did not have the disease. The result was more pronounced in women. However, for people with MS the risk for certain cancers, such as brain tumors and bladder and other urinary organ cancers, increased by up to 44 percent compared to people without MS.
"We speculate that the lower risk for cancer among people with MS could be a result of lifestyle changes or treatment following diagnosis," Shahram Bahmanyar, who lead the study at the Department of Medicine, Solna. "The increase in brain tumor diagnoses may be due to brain inflammation, but this finding may not reflect a real increase in cancer risk, as there is some evidence that more frequent neurological investigations in these patients mean that brain tumors are more likely to be found sooner."
Shahram Bahmanyar, Scott M Montgomery, Jan Hillert, Anders Ekbom, Tomas OlssonCancer risk among patients with multiple sclerosis and their parents
Neurology , March 31, 2009.