Incidence of cancer in multiple sclerosis before and after the treatment era- a registry- based cohort study

Nina Grytten; Kjell-Morten Myhr; Elisabeth G Celius; Espen Benjaminsen; Margitta T Kampman; Rune Midgard; Anita Vatne; Jan H Aarseth; Trond Riise; Øivind Torkildsen

doi:10.1016/j.msard.2021.103209

Incidence of cancer in multiple sclerosis before and after the treatment era- a registry- based cohort study

Mult Scler Relat Disord. 2021 Oct:55:103209. doi: 10.1016/j.msard.2021.103209. Epub 2021 Aug 9.

Authors

Affiliations

¹ Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway; Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway. Electronic address: nina.grytten@helse-bergen.no.
² Department of Clinical Medicine, University of Bergen, Bergen, Norway; Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway.
³ Department of Neurology, Oslo University Hospital Ullevål, Oslo, Norway; Institute of clinical medicine, University of Oslo, Oslo, Norway.
⁴ Department of Neurology, Nordland Hospital, Bodø, Norway.
⁵ Department of Neurology, University Hospital of Northern Norway, Tromsø, Norway.
⁶ Department of Neurology, Molde Hospital, Molde, Norway; Norwegian University of Science and Technology, Norway.
⁷ Department of Rehabilitation, Southern Norway Hospital, Norway.
⁸ Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Norway; Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway; Norwegian MS Registry and Biobank, Department of Neurology, Haukeland University Hospital, Bergen, Norway.
⁹ Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Norway; Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway; Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway.
¹⁰ Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway; Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway.

PMID: 34419754
DOI: 10.1016/j.msard.2021.103209

Abstract

Background: Whether disease-modifying therapies (DMTs) influence cancer in multiple sclerosis (MS) is uncertain.

Objectives: Assess incidence of cancer diagnosis among Norwegian MS patients compared to the general population in 1953 to 1995 and 1996 to 2017-reflecting era before and after introduction of DMTs.

Methods: We performed a nationwide cohort study comprising 6949 MS patients and 37,922 controls, matched on age, sex and county. The cohort was linked to Norwegian Cancer Registry, Cause of Death Registry and National Educational database. We used Poisson regression to calculate incidence rate ratio (IRR) of cancer.

Results: During 1953-1995 MS patients had similar cancer frequency compared to controls (IRR: 1.11 (95% Confidence Intervals (CI): 0.90-1.37)), although MS patients had increased frequency of cancer in endocrine glands (IRR: 2.51 (1.27-4.93). During 1996-2017 we identified significant increased frequency of cancer among MS patients compared to controls (IRR: 1.38 (95% CI: 1.28-1.52): in brain (IRR: 1.97 (1.41-2.78)), meninges (IRR: 2.44 (1.54-3.77)), respiratory organs (IRR: 1.96 (1.49-2.63)). The excess cancer diagnosis was most frequent among MS patients ≥ 60 years of age (HR 1.30 (1.15-1.47)).

Conclusion: Incidence of cancer among MS patients compared to controls was higher in 1996 to 2017, corresponding in time to the introduction of DMT for MS. This was observed more frequently among MS patients older than 60 years of age.

Keywords: Cancer; Cohort study; Epidemiology; Multiple sclerosis; Risk factors.

MeSH terms

Cohort Studies
Humans
Incidence
Multiple Sclerosis* / epidemiology
Multiple Sclerosis* / therapy
Neoplasms* / epidemiology
Neoplasms* / therapy
Registries