NASHVILLE, TENN. – With much unknown about the risks of cancer and vaccination associated with immunosuppressants used in multiple sclerosis treatment, a neurologist advised colleagues to be aware of the potential dangers and take appropriate precautions.
For example, Eric Williamson, MD, of the University of Pennsylvania and Philadelphia Veterans Administration Hospital, said he goes a step further than recommending that adult female patients with MS who take ocrelizumab (Ocrevus) get regular mammograms. Per policy, he also double-checks to make sure that patients actually get screened.
“I know two women who were diagnosed with breast cancer before they began on their treatment because we asked about mammograms,” said Dr. Williamson, who spoke in a presentation about the risks of immunosuppressants in MS at the annual meeting of the Consortium of Multiple Sclerosis Centers.
In regard to cancer as a whole, he said, “it’s unclear if there is any true increased risk in MS patients.” But this doesn’t mean there is no danger, he said, since research into immunosuppressants in other contexts show that they can boost the risk of cancer by three times to as much as several hundred times.
In transplant patients, he said, immunosuppressants are linked to higher rates of lymphoproliferative tumors (such as those linked to Epstein-Barr virus), Kaposi sarcoma, and cutaneous, renal, hepatobiliary, and anogenital tumors.
Research is also hazy in regard to specific immunosuppressants used to treat MS. Two reports published about a decade ago raised the possibility that natalizumab (Tysabri) may have sparked a slightly higher risk cancer in patients taking the drug for Crohn’s disease and MS, respectively; the latter report hinted at a higher risk of melanoma specifically. However, Dr. Williamson said postmarketing surveillance has not detected any further sign of trouble (N Engl J Med. 2006;354:899‐910; N Engl J Med. 2008;358;647‐8).
Another drug, ocrelizumab (Ocrevus), has sparked questions about a possible breast cancer risk. As Genentech, its manufacturer, notes: “breast cancer occurred in 6 of 781 females treated with Ocrevus and none of 668 females treated with Rebif [interferon beta-1a] or placebo.”