While the predictive value of κ-FLC index and NfL separately has been reported, there is to date no information whether the combination of κ-FLC index and sNfL, both reflecting different pathophysiological aspects of MS, i.e. inflammation and neuroaxonal damage, show an independent and additive predictive value for early MS disease activity, which was the aim of the present study. The gene discussed is NEFL; the disease is myeloid sarcoma.