EXTREME 2023

In a study presented at the European MS Congress, researchers have used registration data from Wales to see whether multiple sclerosis (MS) may be associated with an increased risk of cancer.

ECTRIMS 2023: According to the researchers behind this study, MS has long been linked to a number of different types of cancer. Concern has recently emerged about whether the increasingly effective use of disease-modifying treatments (DMTs) may also increase cancer risk.

Welsh registration data

In a study presented at the European and American MS Congress in Milan this week, by researchers from England, Wales and Germany, it was investigated whether MS is associated with an increased risk of cancer. This was done by extracting health data for the Welsh population and comparing this data with the known cancer risk from Epstein-Barr virus (EBV).

In this study, researchers obtained data from The Secure Anonymized Information Lineage (SAIL). This is a database that collects data from 90 per cent of the primary healthcare population in Wales and 100 per cent of the hospital population from 1970 to the present. The researchers used an algorithm that identified people with MS in this population (with a sensitivity of 96 percent).

MS patients previously had cancer

From a population of 4.6 million people, from January 1, 1970 to December 31, 2020, researchers identified 9,586 people with MS. The risk of cancer was higher in MS patients (10.9 percent), compared with the population group who did not suffer from MS (8.1 percent). The first case of cancer also occurs earlier in MS patients than in the rest of the population.

In an analysis of birth cohorts (1930-1960, 1960-1990, 1999-2000) it was found that this effect appeared in those born after 1960. In contrast, the risk of cancer with EBV infection was present in all birth cohorts.

The researchers concluded that MS was associated with higher rates of cancer, and earlier onset of cancer compared with control populations. This increase in numbers appears to be a more recent phenomenon related to those born after 1960.