Risk of cancer with immunosuppressants compared to immunomodulators in multiple sclerosis: A nested case-control study within the French nationwide claims database.

Compared with IM, a 37% increase in cancer risk was observed for IS with indications other than MS and used for a short duration (≤2 years) but not for IS indicated only in MS. The absence of risk for prolonged exposure of IS with indications other than MS is not in favor of a causal relation with these drugs.